All I can say about the tt-01d is don't waste your money on all of the aluminium & carbon fibre upgrades. I got one off a guy who spent a small fortune who was gutted to find it didn't hold its value. Also had the XB Coppermix Silvia & didn't notice much difference once balanced with added weights. I had no idea how rubbish this model was until I got something much better but are glad I learnt with the Tamiya first.
I have the TT02, but...
I haven't bought any upgrades for my TT02, -other than what I think based on experience w/ other Tamiya kits would be most needed. Aluminum steering upgrade, aluminum motor mount and CV joints for the front axles. Otherwise keeping it stock (but my stock kit came w/ a lot of aluminum and fiber towers, etc... ) -so I think i've spent about $140 total including the kit and will have a pretty nice drive-able basher that shoulld handle quite well. By the way I only purchase upgrades for performance not bling ...