Just my two cents worth... I started with a Blade 400 after only having flown on a simulator for 6 months. Sure I had a few crashes and I spent heaps on upgrades too... but the other consideration I think is that if you go for a Blade 400 you will at least become familiar with how a true CCPM heli works complete with a belt!!

I don't think that the belt poses too much of a problem, providing you follow correct inspection and maintenance practices (tension etc).

I know of guys who have flown all sorts of helis (electric) of varying sizes and still bought a Blade SR, but it was a fun thing. I consider the SR as more of a toy than the B400. The bonus is the DX6i with the B400 kit although I'm not sure what comes with the SR.

Like choppers says - it's your call but parts for the Blade 400 - if you keep it stock - are quite cheap. I'm also not a fan of motor driven tails and I believe the tail motor on the SR is troublesome.