I've got a Boardman Comp mtb that has done me well for the last 4 years. Don't do any proper downhills, just along trails and canal towpaths etc. I was doing about 100 miles a week on it last summer and this spring on roads, so I bit the bullet and got a Cannondale Synapse road bike. Great decision. It's got a relaxed geometry, so it's a bit easier on my back. My biggest ride in the summer was 64 miles, in about the same time it was taking me to do 40 miles on the mtb. Still got the flat pedals, but will be going for clipless next year. I use strava. Good tip about turning the internet off