That is a hard call, but can you really get the RS-40 much cheaper than a new RS-45, if so then yah, hard call, but I'd tend to want the new warranty and a fresh lamp. That said, you might want to wait for more data if you can afford to wait.
The below isn't directed at Zombie, as he has the RS-50 and not the RS-45, but this is generally what I have found to be true in these forums...
There are variances in convergence for sure, but the Sony's lens is said to have a focus uniformity issue, this means a default slight loss in sharpness even before the variance.
Couple more points about Sony hw30 vs. JVC RS-45
The RS-45 still should calibrate decent, and at closest throw the BEST MODE is around 1000 lumens!
For 3D, yes the Sony wins, but I think people are being BIAS'd against the JVC's 2D simply because they prefer the Sony in 3D and they want to believe their projector performs better in every category. For Sports, I'll give the benefit to the Sony here as well, but for movies, I don't believe it...
I have seen this happen over and over and over and over again in this forums. As a matter of fact, the number of times I've been disappointed by people in these forums making claims about a projector doing so many things better than another I can't even count on two hands. There is very little UN-BIASED info, it is there, but you really have to try hard to find it.
It is not a dig at anyone, I used to do the same thing when comparing projectors, you have to go into a certain state of mind to become un-bias'd, it's almost like acting, if you don't get your mindset right when comparing projectors, you will instantly favor one or the other and see things that don't exist, we've all done it before, even Art has done it. It's hard not to. I think what most people are seeing in POP on the Sony vs. the JVC is simply processing issues and calibration and sometimes brightness (when JVC lamp dimmed), not ANSI contrast. A DLP with much higher ANSI and a sharper picture is believable to have a little more POP in bright scenes, but for now I don't believe it when speaking of the Sony hw30 vs. the JVC. Do I believe the JVC OTB might look worse than the Sony OTB, yah I do, but after a calibration I don't think the Sony will beat the JVC in POP, I think the reverse will occur, because every time for me, the sharper projector wins in POP, I'm not taking the 1 in 10 bet that ANSI contrast matters going from 300:1 to 450:1.
When I had less experience with the 3 techs (DLP, LCD, LCOS), I had owned a Sony vw70, at first I thought it looked sharp like a DLP, but after you watch it for a while, your eyes start to see the difference, part of the issue is you need to watch the right type of content, and an untrained eye can think anything looks as good as anything else in certain content. Even at first I knew something bothered me about the older Sony, but it took me a little while to figure out that even though the TEXT was super-sharp, the convergence correction was overly-softening the VIDEO. The hw30 is better, but my point isn't that, it's just that a lot of people will say a lot of things about the JVC vs. the Sony, but you really need someone that doesn't have favoritism to look at both. So far I haven't seen anyone make the comparison of the RS-40 to the Sony hw30 or RS-45, so I cannot say for sure, but I'm leaning towards the JVC is going to be the better projector for movies.
Whenever I trust non-pro's (and sometimes even pro reviewers as well are guilty of it), and someone has a projector with a really good feature that does something really well, the projector tends to get over-hyped in other areas and it often turns out to be nothing more than a bunch of BS. I've seen this every time I buy and analyze a projector, turns out no matter how good a projector is, there are still flaws and I can still find one in the same price range that beats it in at least a couple categories, even if it loses in others, hence the tradeoffs.