The Canon 9000 is a good flatbed scanner for slides and 35mm negs, one step under the Epson V-700 and V-750. It'll give great value for the money, but not the best you can do at home with a desktop scanner.
I use a Nikon Super Coolscan 9000 ED for 35mm and 120/220 film and an Epson Perfection V-750 for 4x5 and 8x10 transparencies and B&W negatives. They both do an excellent job fopr their formats. The Epson is not quite as good for the smaller formats as is the Nikon, but the Epson still does a wonderful job for a glass platen based consumer oriented flatbed scanner. I used to own a couple of very expensive drum scanners and used them to scan literally thousands and thousands of film images, and my experience has been that if you learn how to wring the last bit of quality from your film with these two scanners, you can produce digital files that are clearly just a fraction less accurate than with the drum scanners, especially so with the Nikon. If the Epson had a true and precise manual or auto focus feature, it would be even closer to the Nikon quality for smaller formats as well.
For some hard to pin down reason, I go back and forth with scanning software between VueScan, Nikon Scan and Silverfast, which I have installed on several computers with different enabling OS's, any which of one I can attach to and use the two scanners with. I tend to mostly use the Nikon Scan with the 9000 on an old 32bit Vista machine and VueScan on either that or one of my 64bit Win7 machines for the Epson. I never did warm up to Silverfast, despite its potentially deeper profiling options. So, I use it every once in a while to refresh my memory, but it doesn't seem to actually lead to a better scan than the other two, if I am careful and work with a well profiled monitor.
Well, that's what I use, if it helps.
Nikon stopped making their last two models, the 9000 (35mm and 120) and 5000 (35mm only) scannners, many years ago. Whether or not you can still pick up a good and clean Nikon 9000 or 8000 anymore at other than wildly exorbitant prices, I don't know. I've seen near new or "kind of new" 9000's go for as much as $5,000.00 or even more on Ebay and none (in decent condition) that go for less than about $2,000.00. The Epson V-750 and its slightly less expensive stablemate, the V-700 (the only differences are in the supplied accessories and better lenses in the 750) are still available, but who knows for how long? I'd try to buy one now, if I already didn't have one. As for getting a new Chinese slide scanner like the Plustek, or trying to snag a used Nikon 4000 or 5000, or a later model Minolta, it's a matter of the slightly better quality results of the used machines versus the convenience, warantee, modern software compatibility and the almost-as-good quality of the various Chinese models available today. The quality differences between them are mainly in the general precision of build, the whole lighting path, the optics and the electronics, with the stepper motors probably being about the same.
For a wild card, there's always the possibility of the getting one of the Hasselblad Flextight mock "drum scanners" (actually a very high quality CCD slide scanner, some of which take tranny's as big as 4x5) new for about $25,000.00 or more or taking a chance on a genuine good quality drum scanner. I'm not sure if any company any longer manufactures a real photomultiplier tube drum scanner, but if they do, it would cost a ridiculous amount of money and have gigantically expensive and hard to operate software limited to a very narrow choice of computer OS. A used one, being much cheaper, would be a better choice, but the same software incompatibility problems for those are much much worse, and the chance that the scanner is still in pristine condition is remote.
That's about it.
Regards,
David