I bought a cat D 07 full spec gt with sat nav and hr engine with only
9000 miles for £7500 repaired, I wouldn't say that 05 is priced very well at all, so far I've been very lucky with mine just ask for pics of the damage. What you need to remember is the 350z is a sorts car, one problem I did face was getting the geometry spot on, as allot of parts including the subframe are alluminium the slightest bend or twist can throw out everything, and as it only comes with very minor adjusters I could only get mine into spec with an adjustable rear camber and toe kit Whch cost £250! But I had no other option without having to replace everything as no one could see what was causing the problem.
In short answer do I regret my car? NO it's awesome but keep a good £300-£500 towards fixing niggly bits.