Explain thread counts and help me find some sheets, please!

I know the general concept that more threads per inch = smoother, more durable, and more luxurious sheet, but is there an upper limit to this?
I’ve always bought flannel sheets because we tend to keep our bedroom like a meat locker at <50* and I sleep under a pile of blankets and a heavy down comforter. I like the snuggle factor of flannel.
However, we just bought a new mattress set and bed frame for the first time in our adult, married lives and since we’d been sleeping on a futon for something like eight years, this seems like a good time to buy a nice set of sheets.
Somehow, having never purchased regular cotton sheets, I thought the range was 100-200 for cheapo sheets, 200+ for midrange sheets, and 300-350+ for good quality sheets. I look around on Ebay and the 'net to get an idea of the cost of sheets and where to find reasonably good ones for a decent price. On Ebay you see listings for “1500 TC” sheets which are mysteriously selling for $20 :dubious:
Do 1500 thread-count sheets even exist?
TJ Maxx has sets of designer-label sheets like Laura Ashley (300 TC) and Ralph Lauren (350) for $40-$50, no-brand (“Hotel Collection” with no other info on the label other than thread count and 100% cotton) 440 TC sheets for $35, and a shelf of 600 TC long-staple cotton sateen sheets for $90. These last feel exquisite.
I don’t mind going online to buy sheets, but I guess I’d like to know if there’s any kind of standardization for thread counts, if the thread count on the label is often a complete fabrication (ha!), and how much I might expect to pay nice sheets, with hopes to score a bargain. I know in catalogs and at retail a nice set of sheets lists at hundreds of dollars, but I bet like anything there are places to look for a deal.

Help me, Dopers!

The softest sheets I have are from JCPenney, and they’re 350 thread count, I think. I got a set of 400 t.c. from TJ Maxx, and they’re nice, but don’t have the broken-in feeling that the Penney’s ones have. I won’t pay more than 40 dollars for a set (Queen size), so most of them sheets I get are on sale.

In my experience, it’s best to feel them before you buy them. Most sheet sets come in zip-shut or snap-shut bags, so opening them in the store isn’t a problem.

You don’t really need to go much above 250 – I sleep sans jammies on 250-TC sheets and they feel nice and smooth and luxurious.

Go to SmartBargains.com. They have great deals on high threadcount stuff, but also read the reviews. There was one set that looked great, but weren’t durable. You can get a feel for the true quality of the item.

Overstock.com also has great sheets. I have a wonderful set of 1000 thread count that are silky smooth (even after dozens of washings) and perfect for summer, and an equally wonderful set of 800 thread count that have been laundered to a flannelly-but-smoother soft cuddlyness that’s perfect for winter. I believe that the 1000 were $120, and the 800 were $100, and that’s the best $220 I’ve ever spent.

Ditto on the 350-count sheets from J.C. Penney. I’ve bought higher count sheets from SmartBargains and they’re definitely soft, but they’re not smooth, and they don’t keep their shape – they don’t stay “square”.

The set I’m using now from JCP has the jersey-like stretchy insets at the top and bottom ends of the bottom sheet. Even on a thick pillow-top mattress, the fitted bottom sheet goes on easily and it stays on. They’re very soft and smooth, and I think the set with pillowcases was $60 on sale. I love JCP for bed stuff. They ship really fast too – I think it was 2 days on the last order.

When thread count started becoming a big selling point, some manufacturers started inflating the numbers up to 1500. It’s a lie–er, an exaggeration for advertising purposes. I looked around; this isn’t the story I read on the issue, but it’s close enough. Thread count!

That’s kind of what I figured, re: thread count inflation. Something like SPF in sunblock–anything over a certain point is just exaggeration for marketing.
I guess I just don’t have a grasp on how to tell if a set of sheets is going to feel nice after being opened and washed. I house-sat for my aunt and uncle and felt like I’d never want to get out of bed after sleeping on their sheets. However, the company that made them sold out to another and the ones sold under the same name are now (reputedly) terrible quality.

Also, the higher the thread count, the more fragile and thin the threads. So really absurdedly high thread count sheets don’t last very well.

I find lower thread count sheets more comfy for summer. Drapey is nice and snuggly in winter, but crisp sheets are cooler.