Yea I used to buy thunderbolts when I first started shooting a lot(AKA thunderturds if you do a search) I bought them for the price, cheaper than anything else in my neck of the woods, but havent bought any for a LOOOOOng time... they just arent worth it. They are REALLY dirty, on my hands, in my mags, and in the gun, and they are inconsistant. inconsistant = not accurate. I like golden bullets better than thunderbolts, but my bolt action gets light strikes with them, and in my SR-22 they get carbon down the outside and like to spit a lot at the end... its never caused a problem, but with so many choices, i dont but those anymore either.
My #1 fav is CCI mini mags, but they cost too much to shoot all the time. All I buy now are CCI blazers (in the 500 pack, not the 525 pack) and federal's in the 375 pack. All of my guns do well with both of those, though the sr-22 is a little more accurate with the federals. Given the choice I would go with the blazers.