Twonky Or Serviio?

Are they doing about the same thing?

Is one better or have more features.

Also, I have a lot of DVD files mostly in DVD VOB format and some in ISO (DVD).

I want to be able to play this on a rage of devices, but specifically a XBOX360 and a Logitech Revue.

What format should they be in, or is there a good trascoder to transcode as needed?