Buy a few brands and test them out. Record the number of failure to feeds, misfires, and note the consistency of the recoil. Then proceed in buying large quantities of whatever works the best (in your gun).
For me, Winchester Super X and 333 / 555 bulk pack is best in my gun.
Smallest % of failure to feed and misfire, most consistent feeling of recoil.
Other brands had higher % of FTF and misfire, and some brands/types were quite inconsistent to the point of half the rounds in the package would have a supersonic crack and recoil you could actually feel, and some rounds would have no supersonic crack and felt like a mild pellet gun. WTF.
I feed my gun Winchester Super X SSRN 40 grain (1300 fps) and the 333 / 555 white box 36 grain 1280 fps stuff. CCI velocitor is also rock solid, but I don't plink with it due to cost.
(EDIT: Recently chronographed the Velocitors... despite all being supersonic, it has quite a large velocity spread.)
CCI Blazer and Federal Game Shok were the most inconsistent (some super sonic some subsonic, big differences in recoil from round to round). Note, however, that I didn't test large quantities of them because I was immediately turned off by the inconsistent feel.
To address your pricing concerns, Canadian Tire used to sell the Winchester 333 pack for about 13.49ish, and the 555 for 29.99. So for the exact same product you were paying MORE per round for a LARGER package. Wow. This just goes to show you that price doesn't reflect quality all the time. They have since reduced their 555 pack to 20.99. Wal-Mart is still a dollar cheaper, not that that's a huge deal.
The bottom line is, price is important, but it's not indicative of being better.
Some accountant sets the price, you pick the ammo that's best for your gun. If the best ammo is also cheaper per round, it's a win/win situation.
