Yes, it is worth it!!!

Especially if you already have the 9550 card, which is what I have. I was ready to settle for S-video, but found a deal on a JVC with component inputs so I said "what the heck, I'll try it, if it doesn't work, I still got S-video". So I got the adapter, and the difference was amazing. Classic games look awesome on it, and so do the later ones in MAME.
The video is clear enough where you can do simple admin and configuration in Windows. it will still flicker a bit in Windows, but does not really bother me. If you need to modify your .ini or .cfg files, you do not have to hook up a secondary PC monitor. It is not PC monitor clear, but not really fuzzy either where you can't even read the text like in SVideo
Just remember, you are limited to 640x480 resolution if you use the component inputs, but that is plenty for MAME.