I recently used one of these to ourput 1080 on HD-SDI, and it worked absolutely great. There are only two problems I have with the gefen product.

First, the power supplies they send with the unit are not auto-ranging, they are ONLY 120v, and I have seen them get blown up on two shows now. They are a standard sive, 5v supply though, so replacing them isnt a big deal.

Secondly, all the settings for this box are done via an IR remote, and if that gets lost, you are screwed.

Other than those two things, it worked great, especially for the price, if all you need to do is convert to SDI or HD-SDI, without really havign any other adjustments, then this is a good, cheap alternative to an imagepro.