They're all solid formulas, which some similarities and some differences. Which one would be best for you may depend on your goals. What are you looking for out of them? Are you bulking, cutting, recomping, etc?
More for muscle growth. Gonna stack with xgels.
AlphaMax XT and ArA is a very popular stack. I've ran it many times and I have even used that stack with MassMax XT. I know I'm a rep for Performax Labs but there is a reason I wanted to rep for them. I used their products and fell in love. Not only will AlphaMax xt help you with strength, but it really helps with body composition. The addition of forskolin shines here. Everything is properly dosed as well. Users also typically see improved sleep while using it. I'll see if I can find some logs for you.
Keep in mind that results are NOT dependent on supplements. It's all diet and training. If those two aren't on point, I suggest saving your money and spending time learning your body.
I suggest getting input on this thread in addition to reading up on some logs of each. Just don't pick one. Read a few from each.
For a test booster that promotes muscle building....my vote would be OL TES1FY. It has a more anabolic profile than the other 3 products you mentioned.
More for muscle growth. Gonna stack with xgels.
For an overall bulk, I would go with MassMax XT to stack with X-Gels over AlphaMax XT. I would utilize AlphaMax XT more for a recomp or lean bulk. Out of the three you mentioned, I would go with wither Kingsblood or AlphaMax XT. From a muscle building standpoint, those two seem more favorable, from feedback I have read, compared to M-Test. Although the feedback I have read from M-Test regarding libido is better than the two mentioned previously.
More for muscle growth. Gonna stack with xgels.