In reply to trish1968: Later in the summer I am doing a review of crag packs for UKC - we are currently testing 5 different models. Some are quite fancy and expensive, others basic and cheaper.
But overall my thoughts are, as people get lighter and lighter packs for winter and alpine climbing, they aren't so good as general crag packs. Most of us do more cragging than climbing with a pack on, so having a crag pack is well worth it, and much more convenient for that use than a top loading alpine style pack. Then get a light pack for alpine. Shop carefully and two packs might not even cost more than one top of the range (not really) all-rounder.
For example, I've been using this
http://www.ukclimbing.com/gear/review.php?id=865 for about the last 4 years for weekly or twice weekly cragging trips through 3/4 of the year. At 40 quid it was cheap. Has lasted perfectly and means I can keep my lightweight alpine pack for exactly that.