I took a quick casual look for allowances, couldn't spot 'em. Bioware generally stacks with bioware, but not with cyberware; this is the way it's been. I'm sure this is discussed in 5e somewhere, especially since this sort of thing is specifically allowed in Chummer5 (and those guys are pretty good at sticking tight to the rules); adrenaline pump boosts, muscle aug/toner, and suprathyroid gland all stack, up to the standard +4 limit.