I purchased both the Mangroomer and the Remington HC4250. They are both targeted to people who want to shave their heads with clippers and seem to be the two direct competitors on Amazon. With the hundreds of positive reviews, I expected to keep the Remington clippers, as Mangroomer is clearly the underdog, but I am keeping the Mangroomer. Details as to why are below.

I cut my hair using no guard, right down to stubble now, beard and all. Previously, I'd been using the Remington MB200 with a guard, which has been great, although switching to these made me realize I'd been blind to how narrow the blade is compared to the nice wide blade on these, which makes the job much faster.

Here are some of the key points between the two, and who has the edge:
Closeness of shave: If you look closely at the two shavers, the Remington has an extra millimeter or two from the edge of the stationary blade and the blade that vibrates. Mangroomers blade edges are closer aligned, resulting in a slightly closer shave. Basically Remington has a big underbite, Mangroomer has a small underbite. Winner: Mangroomer
Battery life: both clippers get the job done so incredibly fast that I feel this is irrelevant. Winner: Tie? No idea.
Power: turning on both the clippers, you can hear Mangroomers blades clearly vibrate faster. I have coarse hair (on the side of my head still at least!) Remington's clippers caused a little bit of tugging and I was forced to slow down. Mangroomer ran right through it like butter. Winner: Mangroomer.
Blade feel: I didn't think I'd like a curved edge, but it actually feels really nice against the curve of your head and gets the job done faster. This round goes to Remington.
Quality: both are plastic, and feel pretty mid-range in quality. Some reviews called this a lower-end version of Remington, but I don't feel that's the case. Both feel the same in quality and build. Both feel fine in your hand. Tie.
Price: Mangroomer is cheaper.

Overall winner: Mangroomer. I do really wish it had the curved blade like Remington, but I felt that was Remington's only redeeming factor and not important enough of a factor. If Mangroomer came out with a new, curved blade version, I feel it would be a total sweep for them compared to Remington.

Also would be nice if they had a single adjustable guard instead of a bunch of different sized guards to clip on, much easier to deal with and less to keep track of.

If any issues are encountered with the product I'll update. As of right now I'm excited my grooming process will be cut down to about 1/3 of the time.

Rarely am I able or moved to write a review about a product that is completely positive and makes me sound like a company shill. But I am not a shill and I payed full price for this.

I usually buy cheap clippers and, after a year or so, they go bad. I trim my hair close to the scalp, almost shaved. It's how I like it. This thing gets really close. Perfectly close. And it cuts quick and smooth. Not a single rip or tear and my hair is thick. I've never had a clipper that didn't pinch or pull or...

I have very large hands and this machine fits perfectly in it. I can get a good hold at different angles for behind the ears and the back of the neck. It is precise, powerful, and clean.

I have, finally, found the solution to my hear trimming needs. And I mean 'all' the hair, if you catch my drift.

works great, very easy to use. I like the straight cut instead of the curved cut blades I have used for years. battery life is great

Very happy with this razor, now instead of 20+ Minutes to shave, I can be done in 5 minutes.

This is a great product. I use it to cut my hair and my kid's hair. Very easy to use and I love the extra guards. I definitely would recommend it if you want to save money on haircuts and if you like buzz cuts.