I've had a couple of games playing one at low level and yeah it was a realy fun character to play, I had an elven warlock fighter channeling his blast through his sword(concentration needed). A tortured warrior exiled from his homelands for treating with dark powers.
Its a class I wouldn't let a couple of my players use(I DM normally)due to some of the abilities they can obtain, but with a good role playing flair it's got some cool possibilities in the character development/story side of things, eg where do you receive your eldritch powers from, how do they affect the character as a campaign continues. Otherwise yeah the nuke from fingers thing is cool too lol