Evaluation: 
Conclusion: It is the only thing like it and it works
Review: Scanning slides is a very time consuming process. Constantly feeding the slides demands a LOT of time. But this device allows you to walk away while 50 slides are being scanned. This could be an hour depending on the resolution of the scan. This freedom is wonderful. I've found no other combination that does as good a job as this combo, the SF200 and Coolscan 4000. On the down side, old slides tend to stick together and try to double feed. Sometimes successfully, so you get double exposure scans. Sometimes unsuccessfully, so the SF200 jams. I've always been able to clear the jams and apparently the motor shuts offs and doesn't burn itself up. This is good. So even if you are scanning slides 50 at a time, check on the progress occasionally - you may have to clear a jam.
Evaluation:
Conclusion: An asset for batch scanning
Review: Although seemingly expensive, I found this unit extremely worthwhile. I originally bought it to use on my Super Coolscan LS-2000 (it is compatible with both the LS-2000 and 4000 ED and actually comes in the color of either scanner).I bought it to catalog over 2500 slides that date back to the 1970s. I wanted to remove them from the Kodak Carousels and organize them in archival boxes and trays, which I did.
This scanner enabled me to place my long, lost images in a slide catalog program which I can edit with key words and retrieve with ease. When I find an image on screen, its coding enables me to reach into a storage box and find the corresponding slide within seconds.
When using the slide scanner, I did not scan at optimum resolution--it would take too long. I just wanted scans to help me to identify an image for cataloging. When I view my on-screen catalog and identify an image I wish to use as a fine-art print, I retrieve it and rescan it using the best parameters.
The slide scanner will scan 50 slides at a time. When first trying it, several slides jammed. The slide mounts were made of various materials and thicknesses. The slot through which the slide enters is only one size, large. Sometimes two slides with thin mounts would enter. There is a trick I learned from others who have used this feeder. Place a credit card at the entrance to create a more narrow slot. Attach the credit card on the feeder wall with double sided-tape. I found I needed two slot sizes. Once having done this, the slide feeding was just about flawless--although once in awhile I would get a jam.
Once you get the knack, you can batch scan with ease.
