Over at ScanDig they have a review and resolution tests of the
CanoScan 9000F MkII and some Epson scanners (not the v550 that I could see). And important feature is the effective scan resolution and how well the film holders work for 120 roll film if you're scanning that. It is hard to get a flat scan of that size without a glass carrier which can be a PITA. It is typical for scanner manufactures to boast about these outrageous scan resolutions when, in fact, they are only talking about one link in the chain of the optical path or extrapolated scanning.
For example, the 9000F advertises 9600 ppi scan resolution. But when measured for its effective resolution it comes out to about 1700 ppi per ScanDig. So to scan higher than that does not get you more resolution but just scales up the image. In general, commodity flatbed scanners max out in the range of 2400 ppi last I looked which was some time ago.
The V600 is about 1560 ppi and
the V800 is about 2300 ppi effective scan resolution as some data points.