Well obviously no two situations are the same and as I say I'd err on putting in Rafa or LVG as I think the risk is smaller. But plenty of managers have stepped up to big clubs off limited experience and done very well. To add to the list, Sacchi's experience pre-Milan was essentially a couple of years in the Italian third division, George Graham's experience pre-Arsenal was a few years with Millwall, Rijkaard had zero experience when he got Holland to the Euro semi-finals and then relegated Sparta before he got the Barca gig. There are doubtless more but those spring to mind.