I first got Memory Map about 12 years ago, I can't remember the exact cost of it, it was a fairly expensive purchase, but it changed my attitude to how I purchased and used maps. The main reason for buying it initially was that I found myself going though volumes of paper maps each year, so as I've realised now, it made a lot of sense financially. Now I'm the first to admit a fondness of having a stash of maps on your shelf to proudly boast how well travelled you are......but paper or laminated versions have never lasted well with the level of abuse they received from me.
Memory Map allowed me to print off whatever I needed onto waterproof paper, it required a little fiddling with the printer to get the scale and colours correct, but it was almost as good as a normal OS map. The main problem with Memory Map was (and I guess still is..) is that it's awkward to use with Macs. Oh and waterproof paper still needs protecting, inkjet ink will move creating a 21st Century masterpiece that could probably hang in my local library! I use sticky book covering to give a durable waterproof finish that lasts for years.
I stopped using Memory Map a few years ago and reckon it probably cost no more than about £10 a year..happy with that! I had only purchased certain areas of the UK on it, so when I travelled to a new area, I either purchased an old fashioned map (to add to my bragging shelf) or I updated Memory Map.
When the Ordnance Survey (OS) first bought out their "Getamap" service, I quickly realised how good their package was. Admittedly the 1st year or so, they didn't make it easy to use or print, but the system now really works for me. Not only can I look at any part of the UK in different scales, but I can print it off easily too. Once you've subscribed you can also access all this information on their mobile app too. Now I primarily just use the software to print off and use in the hills, but it does actually do so more much this and all for the cost of a couple of OS maps per year!
For me the benefit of printing maps onto an A4 sheet is hugely beneficial, it provides an easy platform to use and and stows easily in your jacket pocket. Papers maps in some form of waterproof case or laminated maps inherently leak at some point and for me are cumbersome to work with.
Another option I use these days is Bing maps, they have an OS option at both main scales for the whole of the UK ....and it's completely free! I mainly use it to access quickly and plan what I'm up to. Viewranger is another go to option for me, there are a number of others too which all have their benefits. Interestingly I've just been in Switzerland and you can get 1:25,000 & 1:10,000 maps on your phone with some basic GPS functionality for free!
Who knows what will appear next month or year, but it can only get better....and cheaper.....