I brought my 2006 Altima 2.5 S last year with 76000km on the clock, now it is just off 100000km. So far I'm impressed. It's been 100% reliable and great to drive. It's not a ground breaking car but I like it, and look forward to driving it every day. I would have purchased the 3.5 had I been able to, but the 2.5 has enough guts to make it fun to drive. If I could change anything about it I'd make the engine and transmission a bit smoother, and put more feel in the steering.
I would completely recommend this car. When I eventually sell it I will almost definitely be buying the 2007 onwards model.