There are entire newsgroups dedicated to this subject, but in general there are 3 levels of quality with scanning, and with each level you will see a significant diff in DMax and actual resolution:
The "consumer" grade CCDS: Epson, Coolscan, Plustek, the minilab scanning modules Noritsu, Frontiers etc etc - they are essentially all the same
The next level is the "professional" flatbeds (Scitex Eversmart) and the Imacon/ Hasselblad Flextight CCD scanners
The highest level are the PMT drum scanners (even within this group there are huge differences between the makes and models)
It is difficult to objectively compare quality at the higher levels because scanning is as much an art as it is a science, esp with drum scanning. There are numerous operator-decided parameters and even the choice of colourspace makes a difference.
Drum scans are best for slides because they can see into the very dense/ dark regions with the least noise. But they are also costly.
The Flextights provide the best price/performance ratio and the market bears this out. If you look around (outside Singapore), you will see quite a few people provide affordable Flextight scans using the top-end 949/ X5. I only scan the keepers that I don't have wet printed and send them out. It's unfortunate but high quality scanning just isn't available in SG. Shriro, the Hasselblad Flextight distributor, rents out one of their scanners, but it is the old, lowest end and obsolete model that only goes to 3200dpi (compared to the 949/X5 at 8000dpi)
For many consumer grade scanning will suffice for most purposes, but while not every image needs a really high end scan, without it you won't see what film is truly capable of, whichis a bummer if you spent a lot on the best lenses.
