to each there own, but i have come to realize i can grow just as much, if not more, indoors, without teh hassles of digging holes, getting bit by bugs, ripped by rippers, plants eaten by who knows what...and the quality...i have put down my shovel, hiking boots, bug sprays, and grow in the comfort of hid's...but i live in the tundra(sometimes feels this way) 3 months of growing season per year...
i guess its a matter of location, if i could get 6 months of od time, or 8, or 12 like some folks have it...then i would probally veg inside and flower outside all year long
so my take on the uk is the weather is not favorable most of the time, or at least this is my perspective of it...i vote for indoors...