We're going to see a lot more billet lowers to avoid the costs of forging platters. CNC can compensate for the minor difference in strength, and make up for cutting out all the metal by eliminating separate operations on other machines. After all, forging aluminum is '50's aerospace technology.
The AR lower/upper doesn't have the strength requirements that a stressed receiver holding bolt lugs has to take - the barrel extension does that job. It's what makes the AR lightweight and accurate.
Checking comment and reviews at arfcom and m4carbine shows a lot of happy customers. Unlike forging, CNC billet machining controls dimensions instead of having to deal with inconsistent wall thickness. Even the best forging machiners have to sort the lots for set up and runs. CNC machiners just chuck up another piece and move on.
Right now I'd say if you like it, buy it. I bought a forged lower for the price, when billet lowers get to $80 and stay there, it will be a real duke em out on the market.