In reply to JDSwain:
From Killin, Glencoe (and probably Nevis Range too) will be much easier and faster to get to than Glenshee or Cairngorm and because the snow coverage is so very good in the west this winter, there should be plenty of easier terrain accessible for your brother. On the other hand, Glenshee's lifts are rarely affected by the strong westerly winds that'll close NR's gondola and Glencoe's access chair. Under those circumstances, the skiing there might be unpleasant in gale force winds but its lifts are likely to run. Glenshee is a bit of an all-rounder really and lots of fun can be had there by any boardfer or skier but it's not Scotland's 'best for experts' ski area. In that respect, Glencoe has more challenging lift-served skiing and NR has more challenging off-piste.