My DS11 is on Concerta. It is a slow-release form and is supposed to last 10-12 hours. It seems to have a very gradual wearing off. We haven't noticed mood-swings. The only side effect we have noted is loss of appetite, especially at lunch. I have heard people say you get more "re-bound" with the shorter acting stimulants in general.
Maybe you are already doing this, but keeping a log of the medication, dosage and side effects (mood, appetite, sleep, etc) was very helpful for us. There were times when DS seemed moody and grumpy, but looking at the log, it didn't seem related to the meds.
I haven't heard of trying the short acting ritalin to find the dosage and then switching to a longer acting one. Even though they are based on the same molecule and may have approx. the same dosage, the delivery system is different, and they wouldn't necessarily have the same effect/side effects.
Good luck.
