It's a tie for me.
For me personally it's a dead heat tie between Tiger and Leopard. My first experience with OSX was installing Jaguar on my G3/300 tower. At the time to me it was amazing. A huge leap forward from os 9.2.2. Though in looking back at it now it was painfully slow. I chocked that up to living in Turkey at the time and being on dial-up that was hideously slow.
Panther on my Sawtooths and Digital Audio was meh, upgrading to Tiger after that was..WOW! It was my main os for the last 6 years-ish until I purchased a G5 with Leopard. Since then I have a macbook with SL on it. (Perfect os of that laptop). And 10.7 on my mini. Don't really like lion all that much, things are just a bit too different for my taste but I manage. 10.5 gets the most use these days on my road warrior.
For me personally it's a dead heat tie between Tiger and Leopard. My first experience with OSX was installing Jaguar on my G3/300 tower. At the time to me it was amazing. A huge leap forward from os 9.2.2. Though in looking back at it now it was painfully slow. I chocked that up to living in Turkey at the time and being on dial-up that was hideously slow.
Panther on my Sawtooths and Digital Audio was meh, upgrading to Tiger after that was..WOW! It was my main os for the last 6 years-ish until I purchased a G5 with Leopard. Since then I have a macbook with SL on it. (Perfect os of that laptop). And 10.7 on my mini. Don't really like lion all that much, things are just a bit too different for my taste but I manage. 10.5 gets the most use these days on my road warrior.