I did Marketmore outdoors last year, but the summer was so pants I was lucky to get 3 or 4 usable cukes from each plant. This year I did one really early one in an unheated greenhouse, and it is doing very well, I turn my back and there is another proud 8 incher (ooh err missus), I have a later sowing also in the greenhouse, and one outside...both look promising with mini cukes on the way.
I grow them in flowerbuckets, 3 canes at least 5ft tall (they need more, or somewhere to sprawl onto), and string tied around for the tendrils to get a grip on, and more string as they get taller.
They are prickly little wotsits, so you need to skin them, but the taste is 10x a shop bought cucumber.
Best picked around the 6 - 8 inch size.