I enjoy when they're on, but I don't particularly miss them.
When he was still using them regularly, I did miss the variety that he used to use -- bunny, crockadiligator, pig, chicken, monkey, giraffe, tennis-ball-on-a-stick, shark, etc. You never knew who would show up! Toward the end, all anyone ever whined for was Sid and Wavey. (Which are both hilarious, but some variety is nice, too!) That could be part of why he got a bit tired of them himself. *shrug*