I recently took an 18 month sabbatical from my banking software development job and it was well worth the risk. I had been working for 11 years. I ended up getting my old job back when I returned because I did not leave on bad terms. I probably would not have if I had stayed there any longer as work and London life was turning me into an angry selfish person in general.
My only regret is that I didn't buy a flat or house just before I took the break. Whilst employers are more than open to the idea of a long sabbatical in my industry, lenders are not. Right now I am earning just as much as I used to but I am struggling to get a home loan despite having an excellent credit rating. They see that hole in your work history and it gives them the jitters. I should have bought a place and rented it out before I went traveling.