Help!

In 1993, my husband and I bought our first house. In 1993, waterbeds were still big fun, so we got a "big waterbed that we bought with the bread we had saved for a couple of years." [Thanks, Billy Joel, for use of the lyrics!] And it was a fabulous, comfy, warm, awesome place to sleep for about 10 years. And then, we noticed that we hurt all over every morning. It was difficult to launch ourselves and our children from the bed in the morning. Yes, we let our babies sleep in the waterbed with us-their mother was far less nervous for their safety when they were snuggled up against her. It's one of the reasons we got a king-sized bed...but I digress.

About three years ago, the above comfy, wonderful waterbed lost its touch. So, thinking that cheaper was at least okay, if not better, we got an adjustable air mattress. It's one of those like an Aerobed, but it's not the brand name. There was a remote that pumped up or deflated the bed at the touch of a button. And then...

The mattress started to leak. Quite a bit. We'd have to wake up at least once, usually twice during the night to inflate the bed. The pump was so loud, we both couldn't help but wake up. I started having daily back and neck aches. So, we bought another stupid air mattress, this one without its own pump, but with two twin mattresses that attach with a zipper, so we have one king sized bed with dual adjustability. We got that mattress fairly well adjusted. And then...

We got our taxes done. Since I'm in school full-time, we'll get a fair chunk of change back when the government processes our tax return. So, now we can afford an actual, piece-of-furniture, non-air mattress, honest-to-God BED!! As soon as we get our tax return. And there are all kinds of beds out there. My husband is extremely low maintenance in almost every aspect of life, but has a little lower back pain now that he's 40. I have back pain quite easily, and said pain can also gather in my left shoulder/neck area, meet up with friends, and give me twisting, horrible pain like crazy until I want to throw up. Thus, we can't have your joe-average, cheap, hard, $200 mattress, I don't think. So, my request for help refers to this...

What kind of bed do you think we should get? All I know is that we would like to stick with the King size, having had a queen air mattress. Any and all replies will be much appreciated! Please respond in the comments. And as always, have a nice day!