2004.5 is when they fixed the tire feathering issue. Feb 2005 build date is when they released the final version of the tranny.

SG motorsports has their non-revup VQ35DE up to 327whp (dynapack) without opening the motor. I think there are thin details about a 340+whp motor they're working on. Both NA.

I just got my 05 Track and I love it. It's a great car and a lot of fun to drive. Very different owner base from the 240sx world. Interior is a little sparse. Still attract attention even though the new ones have been out for a while.