That's not what I'm saying at all! It works great! It just has some trouble with DSi-Enhanced games on some cards... However, I would primary boot YSMenu because the original firmware has a timebomb in it... It will not work after a certain date, but it is removed if you set the date back. So, here are my suggestions:
1. Dual-Boot the original firmware (Primary) and YSMenu (Secondary) until the day comes that you have to use option 2
2. Primary boot YSMenu, and have the original firmware as an nds file that you can launch (For DSi-Enhanced games, Sometimes doesn't work right)
3. Get a Class 10 micro SDHC (sometimes helps some cards run DSi-Enhanced games, didn't work for me
)
There are my suggestions. If you go with the first method, let me know so I can teach you how to assign YSMenu to the multi-media button (makes dual-booting easier.) Let me know if you have any questions, as this is can be a lot to take in.