Looking at all options and possibilities it is probably down to the same thing as everything else in photography, which quality do you want/need and what can you afford.
Personally I never considered anything but the best way to scan my slides as I have also always invested heavily in the camera gear and travel, so I was looking at an option to maintain the quality and wanted to scan the negatives/slides in such a manner that the slides would actually be redundant (although I haven't been able to part with them though
).
If you only want to scan the slides to be able to show them digital or put them in a folder on the PC I guess that other priorities might apply.
One thing I wanted to prevent for sure was investing a lot of time only to have to redo it all again at a later date on a higher quality. For that reason I never used the Minolata D'image scan speed for scanning my collection for preservation but only for showing a scan. When the decision was made to really archive the analogue collection digitally and getting the max quality out of it the Nikon 5000ED came out as the best option. As I have the time for scanning, buying one of the last new scanners was preferred over having it done by a scan service.
In my opinion, although price is certainly a player in the decision making process, it is also good to think about the future and what you plan to do with the results.
Just wanted to share my thought process on the subject in which quality is always the top priority , and it was a process over many years before the decision was finally made.