In reply to davies00:
Following up on what others have said about ideally having two pairs of boots for summer and winter, I'd say (based on 25 years of walking climbing and only recently realising this!) that you really need three pairs!
1. A super-light pair for warm, dry-weather walking. Perhaps even just a pair of trail running shoes. Good also as approach boots to rock climbs.
2. A decent 3-4 season walking boot (Scarpa SLs suit me but Raichle, La Sportiva and others do equally good boots that may fit you better). These are ideal for wet walks in the Lakes, scrambly days on dry rock and will stretch to easy UK winter mountaineering and alpine.
3. A full-on 4 season technical boot for really cold weather and steep ice/mixed climbing (I like my Nepal Extremes but again, a question of fit and where you'll be climbing).
Yes, I could use the Nepal Extremes for walking but:
a) however good the fit, they just aren't as comfortable because they are so much more rigid and higher cut
b) they are hot
c) they are made with softer climbing rubber so will wear out quicker than a pair of hiking boots (also the lack of flex can lead to more uneven wear and an early retirement)
d) they cost much more than my (admittedly dirt cheap, bought in the sale) SLs.
My advise is get a good comfy pair of B1 boots now. Most of the time they will be ideal. They will be enough to try out winter mountaineering and even if you love that and buy a dedicated pair of technical B2/B3 boots, you'll still use a good comfy pair of hiking boots so there is no additional long-term cost, in fact it is probably cheaper.