Based on the tests we did for the Tire Rack and Avon at the end of 2005 and last season (they wanted some feedback to see how the Tech RA performed on several other surfaces in different conditions with hacky drivers

). I found them to be 3 - 6 tenths slower than Hoosier A6s on a 50 second course. Based on testing at the Tire Rack, they found them to be about 3 - 4 tenths slower than A6s. They are closer on asphalt than on concrete. I believe that Tire Rack testing showed that they pulled more lateral G's than the Kumhos and Hoosiers.
The nice thing about the Tech RAs is that they wear really well, work great in the cold, and are hard to overheat (important if you are doing something like an Evo School when you get many back to back runs). Chris P. and I found them to be a good tire, I liked them. They are a bit quirky, very sensitive to pressure changes, and I found it harder to get 10/10ths out of them compared to the Hoosier.
Prior to testing the tires, Chris Harvey at the Tire Rack told me that you really have to "beat" on the tire to get everything out of it - he was right. It was a different feel that took a while to figure out. The sidewall is so stiff that if you drive the car at 95% you "feel" as if you are at the limit and thus don't "feel" like you can push the car anymore. I found (after getting a bit angry and driving harder) that the tire can take a lot of abuse and is progressive. To me, it has a two stage feel on the sidewall flex...when you drive it hard enough it takes its first set when the car leans over, when it's pushed harder it takes second more subtle set (I believe due to the stiff sidewall - though I could be out to lunch on this). Anyway, figuring that out was what allowed to get the time gap much closer to the Hoosiers.
Bottom line is the Avons will be cheaper on a per run basis than the Hoosier and you're not giving up a lot of time, but they are not as easy to drive as Hoosiers or Kumhos. I still think the best "bang for your buck" tire is the Kumho Victoracer V700. I was looking at either buying a set of those or the Hankook Z211 road race tires they are selling for $95/each (ad in this month's grassroots from Hankook dealers) for 205/50-15s. The nice thing is that you can drive to the events on both types of tires.
I've been considering buying something cheaper as well to save money early in the season to help with the diaper and day care fund
Good luck on your decision.
Eric