The problem is that by next year, the models may have changed and the higher priced ones today could be £500 or less
FWIW it is better to get a proper video person for your wedding. If you have a friend who has one or can use one let him use his own camcorder
Just giving your camcorder to any friend on the day may result in hrs of footage of which only 5 min ( if that) will be worth watching .
A newbie will Handhold a lot zoom, pan , talk, try to catch every moment and guess what ? .. You wont like it, trust me on that. You wont find it funny
I have done a few ( including my own Sisters ) and was glad I also got them an official one as he was able to use techniques I had to learn "on the fly"
They are not as easy as they may seem
To guide you Hi def is Good, HDD isnt bad ( some folk are more keen on cards now)
£500 is perhaps not going to get you the "canines tackle" of camcorders but is decent money
Kids come when they want.. not always shortly after the wedding ( unless you know something I dont)

HTH