heres my brothers stumpy a5:
magnetic trigger mod
a trigger stop that makes the pull so short that if my bro runs into something harder than usual he'll blast himself senseless
a stumpy 10 inch dye boomstick barrel (he also has a 12 inch tip)
a homemade suitcase strap sling
low profile hopper with cosmetic-wedge mod
techt squishy paddles
and a 32 degrees ex chamber.... which is currently for sale along with a 14 inch progressive barrel (if interested ..PM me for the ebay link )
he also just picked up a palmer inline stabilizer (for remote setup...thus the decision to sell the ex chamber).....
its madd stumpy....