Cheap strimmer options

After some advice from you gadget gurus    I would like a cheap strimmer for the plot for the forthcoming seasonal gift exchange with OH.

I have no power down there and have seen some very reasonable battery powered models on various sites.  Are they any good and can anyone recommend one make over another?  I only want to trim the grass round the plot edges and other lightweight jobs.  It just takes an age with shears.

Thanks for any help 

£120 would get you a Mitox petrol grass trimmer. They're very good value, and much better than the usual El-cheapo petrol item for that sort of money.
Or as Ice says the battery Challenge seems to get reasonable reviews for what it is.

How long does a Challenge battery charge last Ice?

And does it do edges as well, as that would be a boon on both Plot and Patch...

When I first bought it I could easily do all my lotty paths on a full charge and a bit to spare.  Sadly, I am in the habit of charging it up and forgetting it for a day, so it's not as good as it was.   It's a basic model that doesn't flip so you can do edges, but I just turn it upside down and do them anyway, no problem as it's quite light.

Thanks Ice, it seems a good option here, so will check Mrs Growster's purse, while she's somewhere else looking for the remote...;0)