Mechanical combination door locks are ridiculously easy to get through – there’s even a special tool which you slide behind the face, give it a wiggle, and it pops open. Electronic ones attached to a proper solenoid deadbolt are much better, but you may well run into insurance problems as they’re not a 5-lever mortice.
Mortice locks are by far the hardest to pick. Cylinder locks vary from stupidly easy to a bit fiddly, but still pickable, often in seconds.
In reality, though, a thief will almost never bother with picking or getting through a locked door non-destructively.