Plustek Optic Film 7600i-Ai Film Scanner Reviewhttp://www.luminous-landscape.com/reviews/scanners/plustek.shtml
which compares the 7600i (which is within your budget) with a (discontinued) Nikon Super Coolscan 5000ED, and with an Epson V750 flatbed scanner. Short answer: the Nikon is best, followed by the 7600i, followed by the Epson. But the differences weren't that large.
I have a 7600i. And I also did a lot of slide digitization using a Canon 60D + Canon 60mm macro lens, + PhotoSolve Extend-a-Slide. http://www.photosolve.com/main/product/xtendaslide/index.html
I was very impressed with the results I got with the 60D combination. I think (but can't prove) that the Canon RAW files give me more bits of data than what I get from the 7600i. Resolution-wise, the 60D and 7600i are similar.
If you already have a good DSLR and macro lens, then using something like the Extend-a-Slide is an attractive option. But if you don't, then buying a DSLR + macro lens would be expensive and you probably should go with a scanner.
One big attraction to the DSLR route is that if your slides are in good condition (so you don't need to do extensive scratch and dust removal), then digitizing slides with a DSLR is very fast. Scanners offer IR scratch and dust removal. However, scanning a slide with IR removal (at a usable resolution) takes at least several minutes per slide.
My slides and negatives are in tough shape, due to poor storage, so the Plustek's IR scratch removal saves me time, compared to how long I spend in PhotoShop fixing the damage. (But the IR process can remove image detail, so if you are a stickler for maintaining image detail, then you may not want to use IR scratch removal.)
Negatives are a different story. I could digitize negatives with my 60D, but could never figure out a workable way of removing the orange mask and compensating for the weird curves that different negative film stocks have. For negatives, I stick with the 7600i and VueScan (VueScan knows about a lot of film negatives--this is a big deal.)
It all depends....