Hi Gilly, Like Shelley says, there are dressing services nearer to the NW Leeds and Hull both spring to mind, but I appreciate your reasoning for a trip to London. You might also check out the Brighton area if you don't mind travelling a bit further. Just Google dressing services in the area of choice
I would also echo Shelleys comments regarding Transformations in Manchester. I used them for my very first makeover and came away very disappointed.