NHS nurse here.
I'm seriously considering taking early retirement this year, probably on a flexi basis so working one long day a week. According to the bumf you can take a larger lump sum and a smaller monthly income or a smaller lump sum (almost half less) and bigger monthly income. Most of my colleagues who've done this have taken the bigger income because in their words 'it all works out the same in the end' 
Obviously I'm going to do some research, maybe even get some professional advice but I just wondered what others have done and why ? To give some background I've paid off my mortgage and have a fair amount of savings. One of my sons will be going to uni in the next few years so will require a student grant at some point. Any advice will be really welcome !