With Federal Gold Medal 69gr i think and some PMC silver box (dont think the make it anymore) I would get around .5 to .75" 5 shot groups. That was with a scope at 100yds off a sandbag. Closer to .75" was more of the norm. Im sure it could have done better than that with a better shooter though. On occasion i did luck out with groups lower than .5" but i call that luck with my skill level.
I think for most people the accuracy of the RRA stainless h-bar is probably good enough and a pretty good buy. There are allot of options out now for a stainless midlength that wernt when i bought mine. Overall i would say i would buy it again but wouldnt reprofile it. Cryotreating may help my situation but i dont know if its even worth it cost wise.
BTW: The profile i had it turned to was a spr under the handguards and a m4 in front of the front sight base. I sent it off right when the assault weapon ban was being lifted to have the barrel threaded and reprofiled. I think my screw up was up front. I wish i would have left that front part alone even though it does look good and make the upper look shorter. I sent in a full scale drawing of what i wanted so the screw up was completly my fault.