Thanks again for all the great responses here. I'm happy to report that just tonight I finally made my decision and ordered a king! I went with the Novaform memory foam from Costco (they're on sale this week). I'm a bit nervous -- a bed seems like such a crucial purchase and it's so easy to get wrong -- but I feel like anything will be better than our tired old mattress. I need to decide what sort of actual bed to get with it. Since we previously had a queen I can't use the same box springs with the new mattress. I realize no box spring is necessary, but we don't even have a bed frame of any kind. We may buy a really nice bed sometime in the future, but for now I just want to sleep comfortably! I suppose it will be okay on the floor for a while, but I'll need to think of something pretty quickly. I don't think my poor old knees could take getting out a bed on the floor for too long! Thanks again for your input -- it really helped our decision-making process.

@Emily Finch Uh no. you are severely misinformed I must say. it’s much much more about how the linen is weaved and finished rather than the raw material of the flax. Just as, Italian leather uses cow hides outside of Italy, such as Argentina. But it’d be laughable to say that Argentinian leather is just as good as Italian leather. Another example: Scottish and Italian Cashmere use raw cashmere hair from China (Inner Mongolia region), but it’d be laughable to say Chinese Cashmere knitwear is the same superior quality as Scottish or Italian Cashmere. If the raw material is what matters the most, virtually everywhere could produce the exact same product by just purchasing the raw material of the specified place. But that just isn't so, otherwise these companies would be completely outcompeted already by places with cheaper labor. This is why ”Belgian Flax Linen” (linen woven in China or India using flax from Belgium) is almost always inferior to true Belgian linen (Linen woven in Belgium using flax from Belgium). And from my extensive experience, linen woven in Ireland, or Irish linen, tend to be the finest quality in the world that trumps Belgian linen (on average of course). That being said, unfortunately, Thomas Ferguson no longer produces their "premier" line linen. Because I guess they weren't cost effective for them. Their premier line is the finest modern linen there is next to McCaw and Allen Royal Warranty linen. But it was too expensive to produce and nowadays you can actually find vintage Irish linen (even unused in box) just as fine for half the cost so TF were losing quite a lot of money so they stuck to superior line for their finest linen model (they even told me their superior line is pretty much the only one that was selling). They are now producing more economy line linen that are much cheaper (e.g., chambray linen) but the quality has become much more average as a result. Libeco's Geneva line is actually a bit finer than TF's superior line. The finest modern linen I've found recently that doesn't cost thousands of dollars per set is LinaPlusHome's Italian Lavanda line (150gsm). Everyone should check it out. LinaPlusHome is on etsy. Her Italian linens are absolutely breathtaking you have to see them to believe it.

Like I said you can buy just the fitted sheets from Company Store. Just buy neutral colored fitted sheets and keep using everything else you have. I just wait until they have a sale and buy a couple in a color that coordinates with my upper bedding. Once the bed is made no one can see the fitted sheets anyway. Currently my fitted sheets are grey, the flat sheet is green, the quilt is grey and the patterned pillows are a grey, green and yellow pattern. Sometimes my fitted sheets are yellow and sometimes white, it all works fine. As you can see from their site they have a wide color pallet to choose from. These are the jersey sheets but they also have cotton, sateen, flannel, percale, linen to choose from. For me to buy 2 twin xl fitted sheets is pricey but I don't have to buy any thing else and I can go cheaper with regular cotton or plain white.

I think twins will work - get 2 small nightstands, 1 for each bed though. I’m pretty sure you can fit that, as our guest room is about 1’ less In width and we have plenty of room for 2 tables. Get twin XL, by the way as KW suggests. I bought a strap and filler pad on Amazon (about $40) to turn my twins into a King to use occasionally as needed. I put a nice thick topper on top so no one feels the split area and use King linens. That said - I’ve had a helluva tone finding really nice bedding for twins, XL or regular. Lots of kid themes because it’s usually used for kids. I actually crocheted some pretty need spreads. You may have to look at custom Or altering a Full or Queen to fit.