Salamantis said:
It just offers more features and has great support (Team) behind it.
To expound on that a bit,
The team behind the cyclo is absolutely amazing. They keep in close contact with the people on their message boards, and will do the damnedest to fix whatever problems people find. As well, they are constantly putting out new betas (and new full-blown) firmwares. Currently, their firmware supports (beta) auto-GBA patching. So if you have a flash cart in your slot-2, you can just click the GBA game you'd like to play (directly d-loaded and thrown onto the card, same as NDS games) and they'll be patched, transfered to the GBA card, and loaded.
Also, a new In-Game text reader has been added, which, until now, has only been seen on the Supercard DS 1. With that added on, Cyclo has pulled just slightly ahead of the SC team in my mind.
Also, the CycloDS and the card reader that came with it feel so effin solid. I have a SC-DS1 and a DSTT (that i got and set up for a friend) and the cyclo has a much better quality build.
I didn't think the build and the team could mean so much when buying a card (i had the SC-DS1 prior, then i passed that to the Wife® when i got the Cyclo), but after having questions and whatnot about the card, it does mean the world.
So, in terms of playing DS games, most cards are equal. Even with features, the SC-DS1 has a lot of the same options.
I do prefer my Cyclo to other though.