Thanks to you all for your input - I think I'll give the old Macs G2s a go.

I must admit I've tried a few and have settled on the EasyBoot Epic. It is a bit fiddly at first to get to grips with but once you have mastered it you can put each boot on in about 30 seconds. (My first attempt took about 10 minutes per boot!) Getting them off also requires a knack but a helpful hoof pick works really. The thing that I like about them is that they don't come above the coronet band and hence don't rub. you can buy all the spare parts that you need - I have done this when things have worn out / broken and my two year old took to them like a duck to water. I would say order 1 size bigger - my reining mare measured up as 00 for hinds and 0 for fronts. I have since moved the 0 size to her hind and ordered 1's for the front. See http://www.easycareinc.com/our_boots/easyboots/Easyboots.aspx

It really depends on the shape of your horse's feet. Try ringing the Saddlery Shop as they are very knowledgable and stock all makes. I use easy boot grips as they are less slippy on grass, but I am worried I may wear the tread down quickly on hard ground. I am doing 20 mile pleasure rides at present on good going without boots most of the time and so far have not used boots behind. I use the boots for very stony going or wet grass. Good luck!

We have just got some Cavallo simple boots. They are very good, and fit well.They are easier to fit than Old Macs, and have no parts that would break. However i do recommend using them with their pastern wraps, as they can rub around the top, without these.