I think you should consider more carefully where the technical priorities are. If you are putting probably around a couple of thousand into up-grading the camera, because the image quality and resolution will be that much better, you don't want to find yourself crippled in post-processing with a third-rate application like DPP. You should be using Lightroom or buy an up-grade from CS2 to CS4 and use ACR 5.4. That will balance your post-capture processing potential with the camera up-grade. Then comes the B&W conversion subset (in that order unless your whole imaging life is B&W, which for most people it isn't). Silver Efex is a very nifty and effective piece of software. I have it, I've used it and I like it. That said, I've also done A LOT of B&W conversion straight out of LR 2.5 and ACR in CS3 and CS4, which has survived peer review very successfully. So while Silver Efex has its own set of advantages, you can really do a lot of very high quality B&W without it.