I started going back and playing Sonic CD and Sonic Triple Trouble last night, via Sonic Gems Collection on Gamecube.
Triple Trouble is fantastic! Very fun. Especially now with a save feature. There are some really great levels here.
Sonic CD, however, was worse than I remembered. The Time Travel gimmick really ruins the levels. Not to mention the terrible jump sound effect. However, it is really cool how Amy and Super Sonic appear in the levels, and by the time he kidnaps Amy, it surprises you. I am going to try to get the Time Stones this time, but I'd rather finish Triple Trouble first.
Also, I am also like SuperAngelo64. I used to be a Mario guy, and I didn't get into the Sonic franchise until the Gamecube. Other than a few exceptions, his list hits the nail on the head.