Interesting that you think that of 7.5.3 — it worked, sure, but it could be painfully slow. System 6 was preferable as an OS — MultiFinder was better than 7, at least in the first couple iterations — but much of the software I needed demanded 7. 7.6.x was the first bright spot since 7.1 fixed much of what went wrong in 7.0, & there was a ton of waiting after that. 9 just chugged along for me, for the most part, which was nice.

Loved Snow Leopard too, & was shocked by how bad Lion was in comparison. Glad they got back on track after that.