It seems the new kids on the block are Silk Amino Acids or SAAs, comprised of 18+ amino acids in the entirety. However researchers have found that of the 18, 5 are of particular importance, and when in a precise ration can increase blood concentration of testosterone amongst other benefits. SAAs seem able to increase muscle volume, prevent tissue injury and fight fatigue. The new findings are set to take the supplement industry by storm it would seem......in summary on the current research it would seem SAA's are a precise, well calculated scientific breakthrough with potential for adding strength, building muscle. and enhancing performance.

I'll still be using my Xtend for sure, and it looks like the only SAA supplement available at the moment is BLOX by BPI.

Here's a study i found if anyone is interested

Silk Amino Acids: more muscle, more stamina, more testosterone

Dosage for Blox is just under 4g and comprises of:

SAA Sequenced Proteins (alanine, glycine, serine, valine, threonine)
1 scoop per dosage, 30 per tub. Same protocol as BCAA's pre, intra and/or post workout