i know. I spent 1K on my 3.38 for the e36, and i thought that was steep. The cheapest one i've seen for 335 is like 3K. Ouch.
I'd probably get one with shorter gearing while you're at it. 3.46 or something mabye. Stock is 3.08 afaik, so with a 3.46 you'll be putting down 12% more torque to both wheels. Combine that with software and mabye a wee extra boost, and that will be one fun vert.
How do the e93's feel? I haven't driven the new verts, i know with e46 and even more-so e36, the lack of b-pillars and a roof make the whole car feel a lot less stiff. I wouldn't want to drive one of those with 450 ft/lbs of torque without some structural reenforcement.
Hot: 2001 Estoril M Roadster
ZCP 19's, ZHP knob, JL 8W3
Cold: 2002 TiAg M3 6mt
ZCP 19's supersports, ZHP knob, UUC short shift GROM, OEM 18's w310's,
http://absolutehid.ca hid kit