Thanks everyone for your replies, have had one of those days so only now had the chance to sit down and reply.
G has very good hand / eye co-ordination - I did the banana test and he picked it up and put it straight into his mouth (then made a "yuck" type face 
). He sits up pretty well with support and has very good head control...he's pretty strong - is already rolling both front to back and vice versa.
A couple of my friends with younger babies (just by a week or so) have recently been advised to wean by the health visitor which was why I was wondering if G would benefit. I don't want to do it if it won't benefit him, I'm in no rush, but if he's ready for it then would be up for giving it a go.
I'm quite interested in BLW, have been reading up on that a bit and have watched a couple of videos on youtube, but think we may do a combination of rice/mush and finger foods.
I think perhaps in the next couple of weeks I'll slowly introduce big/hard foods that he can play with and put in his mouth / taste and experiment with, but not actually eat. I'll try to get a bit nearer to 26 weeks before we actually start weaning.
Re: finger foods - he's had melon (loved it), carrot (quite liked) and banana (really didn't seem to like). Any thoughts on other stuff I could give him?