Another option is the Coolscan V ED, which is considerably cheaper than the 4000 or 5000.
It has recently been discontinued by Nikon, but you can still find a few examples out there.
It will last a long time and can still be fixed easily if it breaks, so don't let the "discontinued" stop you from getting one for a good price!
Minolta has some nice models as well, and it's also discontinued.
Both the V or the 5000/4000 will produce incredibly sharp images. Having said that, if you plan to print them at sizes exceeding the usual 10X4, you might have to consider using additional software sharpening.
Remember, this is 35mm film.
The same considerations that stopped 35mm from producing very large and sharp images with enlargers are still there with scanners and won't go away: they have to do with the limitations of the film media itself, not the scanner.
If anything, scanning allows you to apply post-processing software sharpening, something that is not easy to do with enlargers without some fancy masking.