I have noticed a little bit of a change in beds over the past year or so, although the names havnt changed.

I prefer a more springy bed, so my choice is Hilton. Doubletree usually has the same beds, but not always, so more of a gamble there. The Westin/Sheraton beds (I don't notice much difference between the two) are softer cushioning, but harder in the coils. That's why I hate the idea of soft versus firm - I don't want a thick cushion on a concrete slab, I find the springiness gives me more support.

Where can you find "springy" beds in London? The Hilton beds are not the same there.