I have a 1/2" drive Maximum, which I just used today. Mine is the previous rubber handle version - the current ones have a metal handle. My brother has one of the current ones.
I think they're decent, they'll do the job for a weekend warrior. When you can get them on sale for around $60 they're rather good value. But not perfect.
- the older ones had 10 ft.lbs. per turn of the handle, the newer ones are 20. I find the older ones easier to adjust.
- I do sort of prefer the newer all metal construction, as the older ones the ring on the handle with the reading on it was plastic.
- For me I wish they offered a few more models with different torque ranges. The 1/2" drive 250 ft.lbs. is great, but a 150 ft.lb. model would be nice so that lugnuts are right in the middle of the range for accuracy. And because it's such a high torque range, it's quite long and can be a bit awkward. Likewise, 240 in.lb. with the 3/8" drive version is a bit low - I also want something with 40-50 ft.lbs. capacity range.
I haven't looked much at the regular Mastercraft (not the Maximum) models, but I would consider them, I'm sure they're at functional. The Stanley models are probably fine, too, but looked like plastic in the handles and I don't see any point in buying them over the Mastercraft or Maximum models.
I do think they're significantly better than the cheaper Princess Auto torque wrenches, although I can't really say why.
The flexible beam style works and are inexpensive, but ratcheting clicker style is better, particularly in confined spaces.