In my experience, the hookers don't care if it's a $3000 bed or not.
Mattress store guys like to throw lines like, "You spend more time in the bed room than any other room of the house. Shouldn't you invest in a quality mattress?" What you want is a quality feather bed. The mattress is just a utilitarian portion of the bed as a whole. When it comes to making a bed feel like $3000, I've done it for a lot less by buying quality pieces and will be able to swap out my mattress in 8 years without even regretting it.
Honestly,
There are two basic matress types: firm vs pillowtopper models. Aside from the top layer, they're internally the same. Expensive mattresses tend to cost around $1800 and up but you don't really get much for the money except for straps on the side of the coils or sealed coil packs, thicker, smaller coils that are packed close together for stability, or whatever other patented technology the company happens to claim. What saves you is that you don't really feel the coils. You can see how they work in demos, but they all sort of feel similar. What you probably will like is a bed that gives you support, but the case I'm trying to make here is that the average vs expensive mattresses aren't about the coils.
The coils will usually last 10-15 years based on their thickness. Though some may boast 20 years in their warranties, I wouldn't buy that. A mattress that's slept on starts breaking down within a few years of use. What is most noticable on the expensive models are how they vary when it comes to the pillow-topper materials. The top layer in an expensive mattress is usally thicker and the pillow-topper is made of denser foam so it has a more plush feel that tends not to wear out as quickly.
My advice:
Buy a quality mattress under $1000. Be aware that mattress stores expect to make the most money and you might be better off going through Sears or even Sams Club/Costco, etc... Before you say, "I wanted a good quality mattress", remember the mattress isn't what you sleep on....it's just the support system under what you sleep on:"
Purchase a mattress cover($30-50), a featherbed ($100-200) (be careful not to get one that ends up poking you with feathers), and some high quality sheets ($100-300).
Then buy a 42" LCD TV with the money you just saved to hang on the wall in front of your new bed.