After getting my first IS in 2003 I used to have trouble starting it. I'd jump in and just wind the key round and find that it needed a good two or three turns before it started. The advise I got from this board was to get the ignition on and leave it there for a couple of seconds, wait for some of the pre-start checks to finish and then start. No problems after that.
Now I have an IS300 I find on cold mornings, (below freezing) it needs three or four cranks before the engine starts. I have mentioned it to the dealer who asked me to monitor it for the next few days to see how I get on.