If you have a small shop or work out of your garage, these things are great for moving tools around. The single front wheel design functions much better than the two caster units.

Note regarding heavy equipment: After initially using maple for the wood pieces, I replaced the cross piece that supports the single wheel with a piece of metal tube stock. I had to do this because the wood piece bowed under the weight of my table saw (Delta Unisaw with 48" outfeed table). Other than that, I have no issues moving the saw or three other pieces of equipment (band saw, jointer, and drum sander) that are mounted on this base.

I like the design of this mobile base and the price is great. Rockler has a similar one (very very similar) they sell for $70. I'm personally not a big fan of Delta. That company seems to have stalled in technology and new designs about 20 years ago, if not more. The reason I put 3 stars is because when I was drilling the holes in my hardwood everything was lining up and going great. Then on one section the square holes for the carriage bolt did not line up with the round holes on the other side. The only way I could rectify this was by clamping down the hardwood and drilling slightly off center from my previously drilled hole creating an oval shaped hole. It's really frustrating when your putting a project together and suddenly things come to a halt because of a manufacturing defect. Also, the instructions are horrible and of no use. I actually used a google image search and looked at completed bases to see how everything went together. It's not complicated, but still, usable instructions could be helpful. And I didn't receive enough carriage bolts for the number of holes that are pre-drilled. Was I not supposed to use all of the holes? I wouldn't know the answer because the instructions are so blurry and awful to read. It's worth it for the price, just know it may require some modification on your part if you get a bad one like I did.

Got this for my new Craftsman 14" band saw. I used square tubing instead of wood. Not the most stable base I have when moving, as it uses three wheels not 4, but when set down it is very stable.

Make sure you check for all the different vendors in here because this one sells for $51 and there are others of the same model as high as $145..

EXCELLENT! ***** Nice heavy metal with good fitting parts.
Only problem was figuring out the directions on the length of the 2x2's.
Recommendations -
Swapped out 2 shouldered hex head bolts for shouldered carriage bolts on the wheels which is what they should have been in the first place.
Added UHMW washers on either side of wheels.
Added metal washers on either side of pin that goes through foot lever.
Also bored short relief holes in bottom of 2x2's for metal washers for the rubber feet. Allowed better control of final height.

I think this would would better with steel tubing. I'm using white oak with it and there's just not enough rigidity. I have three of these and at some point the wood is going to have to be replaced with square steel tubing.
It works better with my 16" bandsaw than with my 8" jointer. The jointer is within weight specs, just barely. I used very precisely fitted white oak. You can see it flex when the pedal is depressed, and the jointer is just barely lifted off the floor. Just barely.
You should base your judgment, I believe, on how often you will use it and how far you have to move your machine over how smooth a surface.