Friction shifters are fine, the only problem I have with a friction system is that I go down a huge hill on the biggest ring/smallest cog and then have to get down to the small ring/middle-big cog to climb again without losing the 40mph advantage I just got.

That's why they're not raced much anymore, I guess. ;-)

But a set of indexed downtube shifters would be cool...

Enough of me, though. Get a bike with friction shifters, they are also easier to maintain.