Harveys do 1:25k too. I used to be an O/S man and hated using Harveys for mountain marathons, but now I've got used to Harveys I much prefer them. I think having used the large scale 1:40 Lakes map a lot over winter helped. I find the detail much easier to take in on the run. Very much personal taste though I guess.
Yes, I know. Orienteering is proving very, very useful for learning though.
Re:1:25, 1:50, 1:40 etc - yes they do show different amounts of details - I have to say I prefer more detail than less, so am always use 1:25 OS given a choice (filter out what you don't need in your head), however Orienteering has also taught me that you need to get used to lots of differing scales - in my first few events, I got a crash course with different scale maps ranging from 1:4000 up to 1:15k. The trick is to learn how fast you are running across that map - i.e. how much of the map do you cover in a set period of time - if it's a new scale or one you've not used for a while, using nav to the first control often helps with this - the same would apply to fell running - how long does it take to cover that field, or to that stile or to the summit of that hill etc.
Harveys maps can be useful, although I've not used them much - the different colours can be useful for route planning (i.e. going around a hill instead of over it) - orienteering maps are similar to this (diff colours for diff terrain), so I'm coming to appreciate them more.
Personally I think the shading is great - gives an immediate view of the shape of the land, and unlike the OS maps there's never any chance of mistaking a valley for a ridge
Other plus points : different colour contour lines to show rocky terrain; form lines to show the shape of the land between contours; clear distinction between footpaths and rights of way; no parish/county,national trust boundaries to confuse matters; plentiful contour heights marked - no need to work them out by counting or following contours from a couple of valleys away.
The only complaint I have with the Harvey maps is that they don't show walls and fences on farmland - they can be very useful for knowing where you've got to on a traverse.
like many others I grew up with OS and was belatedly converted to Harvey by doing KIMMs. I can't imagine using OS in the hills out of choice now although needs must in many areas. The 1:40 Harvey/BMC Lakes map is, to me, pretty much perfect for fell running either map in hand or taking little room in the bumbag to store and avoids the need for a map case or one of those dreadful laminated monsters whatever the weather. They're also easily folded in any direction to area of interest and have a reasonable life expectancy. And there's Great Calva on the back - what's not to like? As to scale and detail, if you can do a MM off 1:40 then it's good enough for general walking and running use - I think the contour detail often works better on Harvey but agree lack of fence/wall info can be a frustration - I've been mighty glad of the 1:25s for winter mountaineering though. We are spoiled even to be having this conversation when you look at what's on offer in many countries
P
Boundaries, political parish boundaries, tourist information, historical information, excessive walls/fences, many of which are unreliable.
Look at a 1:50k and the major topography just stands out. The harvey is a nice compromise. Ideally a runner should have experience of all 3.