Thoughts on the effectiveness of hot shoe converters?

I own a Sony a100 DSLR and a Metz mecablitz af-81. I'm looking at Nikon/Canon cameras and obviously discouraged to shift because of lack of compatibility between brands (I own numerous Sony lenses, attachments, equipment, etc).

I've been looking at hot shoe converters on ebay (such as this one: http://cgi.ebay.com.au/Hot-Shoe-Converter-Adapter-f-Canon-Nikon-Sony-Flash-/360270066333?pt=UK_CamerasPhoto_CameraAccessories_CameraFlashUnits_JN&hash=item53e1c4f29d#ht_3127wt_807 ) and wondering if you guys have any thoughts on the success of these. I'm just concerned if there may be problems between communication between the flash and the camera (even though you can get a Metz mecablitz af-81 FOR Nikon/Canon camera). Would you guys trust them?

Also, the ones on ebay cheap hong kong ones. If anyone knows a reputable hot shoe converter from a reputable brand (price not an issue) a link would be much appreciated.

I personally would not use a cheap convertor as the camera or flash could be at risk.

Is there a reason you want to switch to another brand rather than upgrade the Sony?

There's no TTL communication between camera and flash using one of these, but other than that, it should trigger the flash. If your flash doesn't have decent manual control, it will be pretty much a waste of time and money.

I use one that adapts the standard flashes to the Sony shoe. With some flashes, it won't fire off the shoe mount flash properly, but the PC socket works. My Metz 32 is like that… I have to use the sync cable to get it to fire reliably. A couple of old Albinon and Sunpak shoe mounts work just fine.