Is the extra cost of the Omega worth it over the DIY/Supergun option? Sure, Omega looks pretty, but costs like 5x as much...
The Omega is now $530 direct from the guys who make them. If you're handy enough you can make your own supergun, but if not an mvs board and cheap supergun + bulky power supply will still cost $200. And if you can only find a cheap supergun which only does RGB, you might need to buy a component transcoder.
You'd be better off trying to track down a cheap cmvs. I've had issues with homemade cmvs and superguns in the past, but the Omega runs as perfect as a console. With everything accepting the video output (unlike some of my consoles with video mods) and a simple power cable instead of a loose ATX power supply in the mix. Plus they come with the latest unibios and built-in memory card. You can buy a unibios chip if you're able to convert an mvs board yourself. But the Omega is much higher quality than an AES and looks nice, so you definitely get what you pay for.