I hadn't seen those two particular devices, but the setup I was referring to works somewhat the same, but by pointing the camera into the lens of a carousel projector, so you get the benefit of active illumination of the slide. From what I could tell, many commercial services use this approach for their entry-level scanning service, though they probably use a commercially-manufactured system, rather than a retrofit to a consumer projector.
Here's a $3500 system
SlideSnap Pro – SlideSnap but there are several youtube videos where people have cobbled together similar technology using standard projectors and cameras, and I recall reading commentary from semi-pros who also use this approach. Some of them spent a lot of effort to get automation, but that shouldn't be necessary and might even undercut the rapid-review and adjustment potential of using a DSLR. I thought I recalled that there are bulbs and maybe even projector lenses made to be suitable for this, but can't find those at the moment.
I didn't end up using any Coolscan post-scan modifications aside from ICE (do I recall that the ICE on the V is not the same version as on the 5000?). I vaguely recall that was because GEM and ROC were not recommended for Kodachrome. I did use the auto-correct in Lightroom for White Balance and Tone when I imported the scans, and thought that significantly improved most scans. Despite some initial learning curve challenge, I became a fan of Lightroom for organizing, reviewing, keywording, and exporting slide scans, and thought the $50 or so paid for Lightroom 5 on eBay well worth it (along with a few 3rd-party free or low-cost add-ins).
When I looked at the results with and without ICE, it seemed clear that ICE produced a remarkably cleaner scan with little image degradation (again, I'm not a sophisticated digital imaging person). However for viewing of typical family slides, I might still think the improvement in color and exposure control and throughput, worth the loss of the ICE cleaning, considering that schmutz is usually not prominent on normal viewing. I think some dirt and scratch clean-up is possible in post-production software, but haven't looked into that.