I agree that Skywards is a pretty poor program in terms of earn/burn etc., but I do like the instant upgrade feature.

You stated in another thread that you were Gold - I have never had a problem with asking at the lounge or check-in for a space-available upgrade: sometimes they make me wait until the boarding, but usually someone finds me in the lounge with a new boarding pass.

Also, on board if there is space and the controller isn't taking calls, and lounge staff can tell me if the flight is full in J/F or not.

I don't think the "peace of mind" of getting it confirmed before is worth getting angry about: that is more of a waste of my time arguing for it when I know I can pretty much get it anyway.

I don't care about the chauffeur drive that you don't get if you upgrade on site - that may be a factor for others.