Yes or No? Help! I don't know

My poor little brain is pickled. We have an important decision to make this week, and I've been trying to get to grips with FPTP v AV. I've read the book sent by The Electoral Commission, riveting stuff, ha ha, and I've been on the aboutmyvote.co.uk website and watched Victor the Voter explain how both systems work. I've read forums to find out what other people think about it, and I'm still non the wiser.

Alternative Voting sounds very complicated, it's going to take ages to count the votes if we move over to that system, and it looks like a lot of mistakes could be made and a lot of recounts will be needed. First Past the Post is simple enough, the person with the most votes wins.

I'm in two minds what to vote for, YES or NO. Is it a case of 'Better the devil you know', or, Let's have a stab at a new system and see what happens'. Oh dear, I'll go to bed and think about it, still got a few more days to decide. Help, somebody please tell me what to do! Goodnight