Rivet installation tools are reasonably priced and, with practice, produce an excellent product. (make double sure the air riveter is a real rivet tool not an air chisel) I believe the reason most owners, and probably many repair facilities choose Olympic rivets is the reduced manhours necessary to complete most repairs.
With a true 'bucked' rivet full access to both sides of the rivet is required. This generally means the interior must be removed to repair any exterior items. That level of disassembly is not generally required with Olympic 'blind' rivets. Simple one-side access is the prime requirement.
There are better blind rivets available which will do a superb job of repairing the A/S aluminum, however, the tools necessary to install are cost prohibitave. Huck and Cherry are rivet brands that make high strength, aluminum binding rivets suitable for any A/S repair. Their cost and the cost of the tools put them in the professional category. Olympic, on the other hand, is owner installable, low cost, effective, and, with the shaver tool, nearly impossible to tell from bucked rivets.
If the facroty is doing the repair let 'em buck the rivets, if you're doing the job, become an Olympic champion and shave after every installation!
If you want to see some alternative tools (and sources of aluminum) and rivets click on this: http://www.wicksaircraft.com/
or this: http://www.aircraftspruce.com/
Hope this helps. 20 years of flying and maintaining Navy Aircraft as well as constructing two experimental aircraft have given me plenty of time to learn the trade.