I tried it out, and it's ok, but nothing iSilo can't do, and do better IMHO. It IS very easy to set up, though.
If you have both, you COULD use mobipocket to get the clipper details for the site(s) you want, then use that info in iSiloX to get it for iSilo (I ended up doing this).
I still like the Mobi reader, don't get me wrong. It's just that I like iSilo so much more...
Regards,
Craig.