Just had a long drive in an R8 and:-

[R8BND]

My R8 is better through bends than my RS4 ever was.... no question.

[rAudiguy]

Love this...... http://www.youtube.com/watch?v=xS_unscao0Q

[R8BND]

Not a huge surprise.....
And you could buy 10 R8s for the cost of a Bugatti too...... or, An R-Tronic and a manual, plus a huuuuge house.
I know what i'd buy.

[RS4SH]

Must be a huge problem for R8 drivers what with so many Bugattis on the road

That R8 following the Viper vid makes me wince every time I see it. Bad line through the corner and no second chances! I was lucky enough to drive a Viper round Snetterton once - thought it would chew me up and spit me out but was suprisingly direct and progressive, even round the hairpin before the straight.

[R8BND]

I watched that it once, that was enough for me!
As for Bugattis..... Common as muck!

[rjkflyer]

So, my two-pennyworth: had a R8 loaner whilst my RS4 was off of the road for two months. (DRC... what else...?)

R8 is a fantastic first attempt at a supercar, full stop.

BUT/and:
1. Needs more power - in reality very little (i.e. only a small no. of tenths) between it and RS4 - i used a stopwatch. Bit quicker top end, but that is driven by more aggressive gearing. Of course it is QUICK, but for 90k i would want a greater bang for my buck.
2. Brakes - MUCH better feel than the RS4. No quibble about RS4 brake performance, but how come the R8 feel is SO much better. The pads, i think you'll find are identical, discs same diameter, although the calliper is slightly different (seems to have strengthening rib) and discs are different design of float.
3. Oddly i find myself more confident in the RS4 in damp/wet. R8 is much more rearward biased which is fine/fun in dry, but saps confidence in wet, albeit that DSP does in fact stop full pant cack.
4. MUCH thirstier than RS4. I was getting 12-13 instead of 16-18 for fast road use. Long run (180 miles) got JUST 20 versus 24.

Would i have one? Of course. I'm an Audi fan. I'd need a Bedford Rascal for the shopping tho...