The eternal double-edged sword.
However, Jim seems a more loyal sort than Jack, for example - we always knew how ambitious he was. His outright stated aim was always to be Scotland manager and he'll do whatever it takes to get there. Jim's always wanted to be St Mirren manager - but he's got his head screwed on as well.
That's not to say he wouldn't be away if a really big club came in, but I reckon he's going to give us at least a couple years, just as he did with Alloa, and wait until he feels he is ready rather than hawking his CV around the middle-order English clubs while his stock is high.