Thomo said:Anyone????
I'll give it a go.
The CAAD8 is an excellent bike. Optimo 1 is the top of the line. However, the CAAD8 has been replaced by the CAAD9. I think (not sure) the CAAD8 will no longer be offered as of next year.
I actually have both a CAAD9 and an alloy TCR. I also test-rode a CAAD8, so I can compare them both.
For me, ALL CAADs are excellent, with the 8 being a very, very successfull model, ridden in the ProTour. The CAAD is lighter than the TCR (I assume you mean an alloy TCR, not carbon) and more responsive. On the comfort side, wheels, tyres and saddle make a great difference, so it's difficult to compare frames. IMHO, the TCR is a bit more comfortable for long distance rides.
Cannondales are known for specializing in Aluminum bikes and they've been making them since the early 80s.
As I said before, when I got my C'9, i test rode the C'8. To be honest, the C'8 felt more comfy than the C'9, but it was spec'ed with 105 and I wanted Ultegra. Since it was not cost-effective to upgrade the 105 to Ultegra, I got the C'9.
Can't say much about Treks, as I haven't tested them.
Giants are amazing value for money.
If the C'8 is last year's, you should get a very good deal from the LBS.
As 99% of the people here will tell you:
Test them all, forget about the brand, and get the one that fits and feels better to you.
cheers