I walked the 2 Moors Way some time ago and absolutely loved it. I assume you're doing it South to North? The only real problem I had was not long after leaving Dartmoor, I hit a point where the OS map was, at the time, incorrect. I don't know what the current situation is, but just in case this is a quote from the Cicerone Guide by James Roberts (which I wish I'd read properly before I got there):
(This is a short distance after Hittisleigh) 'Immediately after the pink-painted Hill Crest bungalow, turn left down a lane into Horwell Wood. The path has been diverted for a short stretch off the forest track ...'. I made the mistake of not reading this bit, and looking for the path where it was shown on the OS map, but when you get to the point at which you're supposed to turn off the road there's no path. This quote above explains it. Of course this was a few years ago so the OS map might now be correct, or the path 'undiverted'. The problem I had was that instead of taking the 'over field' route, I ended up walking some busy main roads until I picked up the path again north of Copplestone.
As already pointed out, don't underestimate what I call the 'middle section', i.e. between the moors. If you look at a large scale relief map of the area you'll see that it's a number of East/West ridges, whereas you're walking South/North so crossing them, with the result that you do a lot more ascent that you'd expect.
You state you've already got accommodation sorted out. That's good because I went with tent (just in case) and hoped to be able to get B&B. I was only disappointed a couple of times but it was early June and out of the school holiday period. There are some sections where there simply isn't much in the way of accommodation.
Look forward to the last few miles into Lynmouth. The day we arrived was wonderful and you're quite high up so get a superb view as you approach the sea. In fact we took a couple of days off in Lynton and then walked the coast path around to Combe Martin which is a good additional bit of walking if you haven't had enough. After that the coast path isn't so spectacular so we got the bus to Barnstaple and train back to Ivybridge where I'd left the car.
It's a great route so hope the weather stays good for you.
S.