Eco-friendly Mattress?

I am super excited because we are finally upgrading to a king size bed! We just put a down payment on a pretty black french country looking bedroom furniture set. I will admit that we actually got the cheapest set in the store because we plan on spending more on the mattress, the part that really counts! We currently have the bedroom set that my husband bought as a bachelor several years ago. The mattress that came with his set is so hard and worthless. Seriously, when we got married I had to buy an egg crate topper to put on it so I could even get comfortable at all to go to sleep lol. We keep saying we need to upgrade to a king size bed so we never purchased a new mattress for the bed we have. Enough is enough, our backs are paying for it more than ever.

As you've been reading on my Healthy Living Event we are slowly changing to organics which includes mattresses! I'm really sad that Naturepedic doesn't make a mattress in a king size otherwise I wouldn't even be talking about other options out there. I am so impressed with the Naturepedic mattress Ethan now sleeps on!

So, we've looked at a couple of brands of eco-friendly mattresses available out there in stores. There is one that we like how it feels to lay on and it does not cost much more than the "regular" type of mattress we would consider purchasing. However, I feel like I need to do a little research to figure out how eco-friendly some of these brands are. Does anyone have experience with any eco-friendly mattresses or heard from someone that has? I would love to hear any advice!