Ultrasonic Cleaner - if unsafe, why does John Brozek say it's safe?

[SLR]

I'm lazy when it comes to cleaning my watch. I don't feel like using a toothbrush or paintbrush or anything. I'd rather stick it in a cleaner and be done with it. BUT ONLY IF IT'S SAFE.

This link has a bunch of posts that say it's unsafe for the seals or movement or whatever reason...
http://www.rolexforums.com/showthread.php?t=12535

So why does John Brozek advertise the GemOro "Sparkle Spa" Personal Ultrasonic Cleaner on QualityTymeAuctions on Ebay or on his own site?

"Description: GemOro "Sparkle Spa" Personal Ultrasonic Cleaner.
* Great for cleaning Jewelry, Watches, Bracelets, Small Tools, Eye Glasses, and more! "

I'd love to use this, but only if it's safe - anyone know for sure?