Sim - not bad for bad weather days and times when you really can't be arsed going down to the airfield. It's also not a bad tool to get the eyes used to a bit of IF. I also found, as a late-stage SPL, that the sim bears no resemblance to the feel of the real thing. I cut back my sim time dramatically about a month after starting flying lessons, when it became clear to me that the sim felt so different to flying for real eg. thermals, turbulence, winds etc. Good luck in your training!