I use auto save. I have it set ofr every 20 changes. Never had a problem. Even if you hit Ctrl+s, it's still gonna take the same amount of time to save, no matter how you save.
 
I also use my own version system. Just in case.
 
And even though I use auto save, I still use Ctrl+s almost after every edit!!
 
We maybe a little paranoid. I wonder what made us that way!!

Grem
 Even if you hit Ctrl+s, it's still gonna take the same amount of time to save, no matter how you save.

Yes. The difference being I know when that's gonna happen.

+1 for Ctrl S. I also use 'save as' every time something substantial is completed (the revised filename documents what happened ).

I find Ctrl+S cumbersome.
I set the ` key (backtick; whatever it is with the tilde, right below the escape key) to "save" in keyboard shortcuts.
and Ctrl+` for "save as"
Quicker, cleaner, leaner, meaner; for me.
I still miss the "save" icon on the toolbar, just me.
I don't use "auto-save".
Long time user, just getting used to "versioning".
 
Tom

And back things up with Gobbler too. It gives you a revision history. Not as finely grained as autosave or CTRL-S'ing yourself, but at least if things truly screw up you can go back to a version from a little earlier in the day. 

There are a couple of points regarding the above posts.
 
Firstly, autosave only ever kicks in when the transport isn't running. It won't try and save when you're playing back or recording.
 
Secondly, I'm curious as to why a project takes 15 seconds to save. The vast majority of mine save almost instantly, and this includes projects with 50+ tracks, 15+ vsti's, V-Vocal clips, 100+ Fx plugs etc. The only project which does take longer is my orchestral template, but this is a monstro project containing 135 tracks of Midi, audio, drum maps & multiple instruments loaded form EWQLSO platinum.
 
So... you need to work out why it's taking so long to save - maybe an idea of system specs would help as well as an idea of what your project contains.
 
FWIW, I'm in the Ctrl + S camp. 
 
 

Bristol_Jonesey
There are a couple of points regarding the above posts.
 
Firstly, autosave only ever kicks in when the transport isn't running.

Correct. It always does it when we're into really concentrating on editing.
That's why it's a PIA and I have it turned off.

Another ctrl-s fan. Whenever something big is performed you can strategically choose when. I also happen not to rely on undo, so when a big change goes awry I simply close and reopen the project and know where it was.

If it's a lengthy editing session, I always start by doing a 'save as' with a different name but within the same project folder so I always have something to return to.

Bristol_Jonesey
If it's a lengthy editing session, I always start by doing a 'save as' with a different name but within the same project folder so I always have something to return to.

Yes, I always do this when an idea strikes me that I know will lead me down a very different path. Thankfully we can have the names very long!!