Super tough dot sight. Sightmark always delivers a lot in quality and performance for the price you pay.
This is their best example of that.

Put this on my HK243 SAR. I own a 340 acre ranch with lots of unwanted predators and ground squirrels that seem to mass in the early evening, raising hell with my livestock. This unit puts an accurate, bright dot on target. Since the shooting often is 50 yards, 75 at most, it's a perfect fit. Good value, well made. Great seller.

I like this 2 MOA red dot, I thought it was going to be a just another cheap red dot but i was surprised at the quality and crispness of this sight. I cannot speak on the battery life as of yet but i can say this is a vast improvement over the older Sightmark red dots. I picked this sight over the black spider red dot as price at the time of purchase was almost exactly the same. I have kept zero so far and walked this sight onto target with a screwdriver quite easily. I may purchase a holosun soon but wanted try out sightmarks newer optic and the more i use it the more i like it. As another reviewer said this is not an aimpoint killer but for under 140.00 bucks its a great choice for a plinker range rifle. It comes with an absolute co witness mount and i would suggest blue loctite on everything when you purchase any type of budget red dot so you will not have a hiccup at the range. Mounted on a 16 inch Palmetto State Armory AR 15 and usually i shoot 50 to 75 yards with this accurately.

Received my Sightmark Wolverine CSR last night and I'm extremely impressed. Range time will tell for sure, but so far it looks like a bargain for only $129 delivered to my door. I've owned or used almost every model of Aimpoint, EOTech, and ACOG at some point in time, as well as several of the popular $99-$399 "budget" red dot/prism/reflex sights from Primary Arms, Holosun, Burris, and Vortex, and this one blows away the rest of the "budget" competition. If you slapped a Burris or Vortex sticker on this sight, people would pay $300 for it all day long, and then come here to brag about what a good deal they got. 

Initial observations: 
Sight comes in a high quality heavy weight cardboard box with full color printing and matte finish that clearly looks like it was designed and printed in the US - just as fancy as anything from Aimpoint or Trijicon. Not the usual flimsy paper thin box with glossy finish and broken English that you're used to budget red dots arriving in. The inside is padded with static free high density foam, with a cutout for the sight and accessories. Once again, the owner's manual is of the same quality you would expect from the American or European manufacturers. Also included with the sight is a picatinny mount with riser and 2 sets of screws, allen wrench, cleaning cloth, really nice bikini cover, and Energizer ultimate lithium battery. 

Likes: 
Sight appears to be high quality and heavy duty. Completely sealed, nitrogen purged, fogproof, waterproof. Well built, fit and finish is excellent, all the machining and threading is flawless and free of tool marks. The rubber armor and retention lanyards on the caps is a nice touch. Glass is clear and I love how it doesn't have the blueish or orangish tint that most other budget sights have. Also love that the power and brightness adjustments are buttons (easy to press, distinct and audible clicks) instead of the Aimpoint style wheel. Windage and elevation adjustments also have distinct and audible clicks. Dot is crisp and bright, 50,000+ hour battery life on setting 6 (which is more than bright enough for most conditions), truly parallax free, unlimited eye relief, automatic shut off after 12 hours.

Dislikes: 
So far, my only 2 complaints are the same 2 complaints I've seen mentioned in some of the other reviews that were otherwise positive... 
1. It's pretty heavy for a micro/compact red dot (~10oz vs. ~6oz for a Aimpoint micro T1 with mount and battery). Some of that is due to the mount (which is solid as a rock, wish there was a slimmed down option available) and the fact that it uses a AA battery instead of some little watch battery (which I appreciate, the convenience is worth the extra weight there IMO). 
2. The emitter is visible around 4-5 o'clock, about as much as it is on Holosun and Primary Arms red dots. Not a huge deal, you forget about it and don't really notice it once you start playing around with it and focusing on what you're aiming at. Sure, it would be nice if it wasn't visible at all, but you're not gonna find that unless you spend a few hundred more dollars. 

Barring a complete meltdown once I get a chance to take it to the range, I would definitely recommend the Wolverine CSR to a friend and will be buying another if I build any future AR pistols or rifles that aren't high speed low drag enough to justify a $600+ sight. Will update this review with performance results after I have time to put it through its paces.

The cheap red dot and it's philosophy of use.

Look at what you're buying...This optic falls into the same area of quality as some of the votex, bushnell, and primary arms red dots available on amazon. This is not designed with milspec standards or extreme ruggedness in mind. If that's what you're after, you wont find that with this optic. However, for 95% of the prospective buyers looking at red dots in the $100 to $200 price range this is going to work just fine.

Here is my experience...

I use this red dot on my fun-gun which is an 9mm pistol and I am plenty happy with it. Aesthetically this optic is pleasing and (in my opinion) works on my platform. The 2 MOA red dot and glass are clear and it's a decent FOV. The optic was fairly close to zero (took 1 magazine) after mounting and has remained zero'd after about 1,000 rounds. Color me impressed with a cheap red dot!

I could have gone with a more expensive reflex sight which is designed with the milspec standard and ruggedness but why bother? I am likely never going to be in a situation where I wished for that $500 to $900 optic mounted to my rifle/pistol. For me it was a budget conscious decision... More time shooting and having fun and less time sidelined (broke) because I spent too much on the milspec red dot.

Final thoughts...

Pros: Cost, Mounting Options included in the box, and Glass Clarity

Cons: It's a tad heavy, the rail mount is what your pay for (**see update**), and it has a large profile

-edit-

UPDATE - Nov. 13th, 2017

This optic just moved from the I like category to the 'I am very impressed' category (see picture). Recently, while on a hunting/backpacking trip my pistol (which the Wolverine is mounted to) had an accident. The firearm fell from about 35 feet over some rocks and into a perennial stream. There were two accessories attached to the pistol when it fell... The only accessory that 'survived' was the wolverine and even after a mostly broken trigger and completely broken trigger guard this optic managed to hold zero...

While there are things that out of the box may seem really cheap with this reflex sight I can honestly say this red dot is tough enough for just about anyone and it's earned another star in my review.