I have both an Epson 3490 and Epson 4990 and have no complaints about either. The 3490 gets the most use as it is my general workhorse, with the 4990 being reserved for slides and negatives. Both handle the "depth" of cards in slabs quite well. I worked my first 3490 to death (thousands upon thousands of scans), and when it finally seized up, picked up another one used for about $30 and I'm off and running again
I also have a Mustek ScanExpress A3 that I use for large-format photos and prints (larger flatbed scanner, takes up a lot of desk space). I would NOT recommend it for slabbed cards, as the LED scanner does not handle "depth" well. If it's flat against the glass, it works great, but even that small amount of separation from the card being in a slab will cause the scan to be slightly blurry.
Based on my own experience, I would recommend any Epson scanner, though there certainly may be other suitable manufacturers.