I've got the smaller of the Eydon kettles. Quality is excellent and reputedly better than the Kelly. It's defintely better than the little Ghillie I have also recently got.
The base of the Ghillie doesn't fully insert into the base of the Ghilie when packing it down. This means the Eydon (which holds around twice as much water) is actually shorter when packed up (though fatter). The extra fatness of the Eydon also makes it more stable and means you can cook more with the cook kit. I get around 3.5 big mugs out of it.
Overall I'd recommend the Eydon. The quality of the Ghillie isn't bad, but it's genrally a little flimsier than the Eydon and the way the hole had been cut on mine left an uneven rim that made it difficult to pack the base in the the top until I had pressed it down here and there and smoothed things off. That really wasn't great. You do get a little nylon bag and whistle with the Ghillie though.
I'll do a more detailed write-up when I've had more time to play with the Ghillie. The Eydon has been very impressive so far, even working fine with damp sticks etc in rain and hail of late.
One final point: the Kelly has two holes in the base as opposed to only one on the Eydon and Ghillie. I can see this being an advantage overall both when lighting and for getting a good draught, but have no experience of this. It could make no practical difference or even be a disadvantage. Others comments could be helpful if they have used both types.
overall - bulk apart - they're great beasts. Take very little to learn how to use effectively and mean you need never run out of fuel again.
Cheers
Mike