Can I send it back to SL?

[milomak]

Each progressive release seems to slow my mbp more

 

[bwana]

Most likely but since apple stopped supporting SL a while back so it would be about as advisable as installing XP on a PC.

 

[vinodh]

Each progressive release seems to slow my mbp more

It depends what MacBook Pro you have. The 2011 versions were the last ones that supported Snow Leopard.

If you want decent performance, get an SSD and clean install El Capitan. You won't regret it.

 

[milomak]

It's a 5,1

 

[vinodh]

A clean install will help. Should make your Mac a bit more responsive.

However, I still have a Snow Leopard restore image saved somewhere. I made it a while back and it works by just imaging it to a partition and then you can boot to a fresh Snow Leopard installation.

 

[Synaesthesia]

Get an SSD

 

[PostmanPot]

Get an SSD

Or SSHD if budget is limited/space is needed.

Also max the RAM, of course.