Quoted:
30Cal, how do you like the A1 Modstock as compared to a PINNED adjustable (VLTOR or otherwise)?
-B
i guess they are both somewhat inconvenient in their own ways.
if you know that you're going to be shooting in BASIC positions (offhand - standing, kneeling, prone) and you have one setting that works for you in all three, then go with the pinned adjustable.
some positions are just downright uncomfortable with an a1 length stock ... like rollover prone and "brokeback mountain" when shooting through small portals in barricade situations.
this is brokeback mountain (as termed by kyle lamb) - it's hard to see but the shooter here is engaging a target 100 yds down through a very small portal in the bottom of the barricade.
i didn't feel like dealing with the extra tinkering on (or the possible legal harassment arising from) the retractable stocks, so i just got an a1 and work around it.
i can sort of do this because i have several pre-bans with magpul ctr's.
as always, YMMV.