The way he was playing, he should have been able to beat Baggy quite handily, and the Soderling match may not have been closer than the Dolgopolov match turned out to be (especially with the error strewn Robin we saw towards the end of his run). Nadal would have been his biggest threat, so you are right to point out that luck seems to have favoured him - but at the same time it appears that Ferrer is painting the lines with winners and aggressive returns of serve too. Plus, I doubt how much resistance a Nadal with an injured hamstring would have been able to provide anyway.
On the whole it has been a nice draw for Murray, but he could well get a similar draw at a future. While I agree this is looks like the best chance he has had so far, I would rather not make bold statements like 'now or never'. He is still on the right side of 25 years old and I don't think he has reached his peak quite yet.
You are right, but 25 is really a prime year in tennis. He has never seen a draw open up for him like this one has. Fed, Nadal, Nole will still be around for another 5 years so Murray really needs to dig deep here, I believe