This is up to you.
You could have presets that you use for recording with everything on.
Now for use with real cabs you could have:
presets without any cabs blocks.
Presets with cab blocks that are bypassed.
Turn the cab sims off in the Global Menu, all the cab sims will be turned off throughout the Axe.
The issue may be your power amp modelling. If I have to use a guitar amp, as I use global amp blocks (1987x,at the moment) in my main use presets, it makes life easier. As they are global I can turn the power amp sim off and it will happen to every 1987x (or whatever amp) that is linked to Global Amp 1.
So in the unlikely event that my power amp and FRFR speakers blow up, all I need to do is:
1. Wheel out the back up combo and plug into the effects return.
2. Go to the Global Menu and turn my cab sims off.
3. Got to my preset and turn the Sag down and save it.
4. Carry on rocking, safe in the knowledge that Saint Cliff has thought of these things to make our lives easier.
btw, I hope you're not going straight into a desk. If you are i have another solution for you.
I hope this all helps.