Purchasing a V35: If i were to buy one again, i'd definitely import it. As Andrew says above it would be extremely rare to find a genuine low km V35 in the country.
Fuel consumption: i found while owning one was quite good. Whilst i used to drive quite spirited i still managed to get around 500km to the tank.
Servicing cost: whatever the cost of oils and filters. I always serviced it myself.
Parts: cost of parts is what you'd expect for an import. in saying that, parts are never cheap.
Insurance: my insurance was really expensive, 21 yr old with loss of licence. cost me $2200 per year with RACQ which was the cheapest quote i got between a whole bunch of companies.
ADVICE: if you are in the market to buy a V35 i'd definitely try to source a 2006-2007 model which has the upgraded CD009 gearbox. Reason being, the CD001 (2003-2005) is well known for having 3rd & 5th synchro issues after travelling around 80,000km (at least that's when mine shit itself) and have the projector beam headlights with a couple of other goodies.
I unfortunately sold my coupe a few months ago but i tell you what man i was definitely not happy to sell it. It's the type of car that you can easily fall in love with. In my work i drive different cars all the time so they don't really excite me - but owning a V35 is definitely something i'd consider doing again. The thing i love most about my old car is that it was unique, powerful (for a N/A) and a real head turner.
I'd get compliments all the time, it was great.
Reliability was great, apart from 3rd and 5th gear shitting themselves i had not 1 drama with the car in the little over a year of owning it. The VQ35 is an awesome motor and i have seen the Americans do over 200,000 miles in them which is amazing.
Goodluck with your purchase.
P.S Don't put Infiniti badges on it when you buy one..