Does anyone have any experience of sound recording?

I need to record speeches etc... at weddings and other events, in large rooms and even churches. It needs to be a solution that I can set going and have wide enough pickup for me not having to worry about moving it all the time, use AA batteries and record upto 2 hours in one go without me thinking about it.

I have been looking at units like this but that seems to be a very expensive solution for what to me seems to be quite a simple problem.

Any hints or tips on getting a cheaper/better solution going. I already have a Rode VideoMic which I have found is quite good for directional stuff.

Cheers

Cris.