Looked at this before for this winter, but ended up on a BASI course instead. But might come back to it next year.
Cant talk from peronal experience. But I've heard allot of people talk highly of Glenmore Lodge at Aviemore regarding Winter Skills.
Their 3 upcoming 5 day Winter Skills courses start on 12th, 19th & 26th of March. Mon-Fri.
The cost being £575 for the 5 days per person.
Glenmore website with more info. [
www.glenmorelodge.org.uk]
If Fort William takes your fancy then another one to check out is Rob Johnson, he costs a slightly friendlier £350 per person for what I beleive is the same course. And I beleive they head up Nevis Range if its open for segments of the course. Not sure on dates though.
His website: [
www.expeditionguide.com]
Im sure theres more knowledgeable folk on here but hope that helps.