Quick list of 10 off top of my head, which I'll almost certainly want to revise immediately.
1. Beinn Alligin (Torridon)
2. Slioch (Letterewe)
3. Ladhar Bheinn (Knoydart)
4. Suilven (Assynt)
5. Cir Mhor (Arran)
6. Beinn Dearg Mhor (Fisherfield)
7. The Saddle (Glen Shiel)
8. Garbh Bheinn (Ardgour)
9. Ben Lui (Tyndrum)
10. Stob Dearg (Buachaille Etive Mor)
But then I've missed out Ben Starav, The Five Sisters of Kintail, Beinn Dorain, Schiehallion and countless others. Impossible!