Hi Phoenix and all,
I wanted to report back.
We ended up going with a mail order option via one the links you supplied: the Dreamfoam natural latex.
www.amazon.com/Ultimate-Dreams-Natural-Latex-Mattress/dp/B008E0LZLG/ref=sr_1_13?s=home-garden&ie=UTF8&qid=1371712846&sr=1-13
We needed two mattresses -- one for the day bed and one for the trundle underneath. Since the trundle needed to fit under the bed, we needed a low-height mattress for it. Additionally, I needed the mattresses delivered in a specific three-day window when I'd be working from home.
Luckily, I had some fantastic customer service from Chuck at Dreamforce (which is, based on my paypal charge, is also known as Brooklyn Bedding).
We are totally thrilled with our purchases.
Here's what he did:
- He was able to build me a custom 6" tall mattress (their usual twin is 10"). It helps to be working directly with the manufacturer.
- He gave me a discount on that shorter custom mattress since it had less latex in it. That's what I call customer service.
- Free shipping is awesome. Shipping on most mattresses is ridiculously expensive.
- The delivery arrived exactly on time, when I was at home.
- Since I'm a WU member, he gave me a free pillow for each twin. Very comfortable pillows too!
- The mattresses were a "6" on their comfort scale and feel great! We're excited to have our guests stay on such a wonderful mattress set. (Our goal is to lead by example so that our family members and friends also get good-quality mattresses for their guest bedrooms.

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It was fun getting the mattresses all compressed and rolled into boxes that were about 1/5 (or less) the final volume of the mattresses -- and then watching them expand once opened. Very cool!
The only small quibble is that the 6" mattress has expanded a bit to more like an 7-8" mattress, but it still totally fits in our trundle, so it's not a problem. It feels great by the way, and no one will even notice it's a few inches shorter in terms of comfort.
Overall a fantastic experience! Thanks for the help Phoenix and big ups to Chuck at Dreamfoam/Brooklyn Bedding.'
This is the best mattress site EVER.
B.