It's sort of like vehicles. I mean a Chevy Cobalt will get you around town as well as a BMW. It's mostly just a matter of budget and personal tastes.

CNC machines have really made buying a good, functional lower really easy. Most mil-spec lowers are going to build out and function just fine. The roll marks and finish on the cheaper ones might not be as nice as some of the more expensive ones.

You do get some extra features on some of the more expensive models. Things like flared mag wells, ambidextrous features, built in oversize trigger guards, QD sockets, etc.

And, like most things, you are going to pay for the name.

Find one one that has the features you want at a price you can deal with and go with it.