I'd read this first before deciding on a mattress.
Mattress Reviews
A mattress is probably one of the most subjective thing you can buy. The wife and I went with the Simmons Beautyrest with a Euro plush top. It's just slightly thicker than a plush top alone. Very similar to the W hotel bed and at first, it felt better. Firm and supportive yet soft at first but ended up being too bouncy compared to the Beautyrest. Just try it out at the store and ask what the comparable W bed is so you can get an almost side by side comparison.
On a side note, mattress stores are quite shady. If you think buying a car was shady, mattresses are seriously marked up. We ended up paying about $1400 which we didn't think would happen on a $3K priced mattress. And for those price guarantees, you can just ignore them. All mattress although the same from store to store are just named differently therefore you can never get a price match. If you read the coil counts and specs, they are the same, just named differently to protect their price guarantee offers. The stores however know exactly which mattresses you looked at since they have a database that cross references each stores mattress by name. We purchased at Sleepy's but this is true of most other places we looked at.