Wow, I really appreciate all of your guys' input. That really helps so much.
I will mull over my options now that I have a much better head on my shoulders thanks to your combined information.
If I do get them dry cleaned, I'll let you know how they turn out.

But when you say it's unnecessary, do you just mean the cost? 
Because a $7 cleaning cost is really nothing to me if it alleviates my worries. Especially since it's the first wash.

If you mean something else, please do elaborate. Thanks a bunch.

Ok, this is a huge help. You clearly know a lot. Thanks for being a good samaritan!

Even if they press the jeans at the dry cleaner, won't the same creases quickly return with wear? That's always been my experience with dry-cleaning jeans with more normal-weight denim.

Also, I just searched around, and I can't find a Denim Care thread. Can you or anyone else reading advise me where it is? If a moderator moves my thread there, I want to know where to be able to find it! Ha! Thanks.

Does anybody else have any experience with the creasing/fading problems I described upon washing? Anybody know anything about results with the different types of washers I described?

I'm very grateful to finally be able to get some much pondered concerns solved!

Hey,

I just joined the forum to try to find out about something I'm stressing about, but I also don't see a way to just search for a certain topic. (Is there a way to do this that I'm just not seeing?) So I'm just going to explain my issue and hope some of you might help me out! I asked Giles, and he suggested I ask here, so here goes.

I've got some pairs of Iron Hearts, and I've got one pair (461 to be specific; not 461S) for which it's become high time to clean. I got these ones in Japan, and I don't think they're sanforized (hence the absence of the "S" in the numbering). But I think they might be of the one-wash variety. I never washed them or soaked them before wearing because the people at the shop in Ueno, Tokyo, hemmed them right there for me. This is one minor reason for my fear about washing them, but again, I think they are "one wash," so I'd hope they'd stand up okay to water. I also think they are waxed (maybe?), because they have a shiny finish that my other Iron Hearts don't have.

Here was Giles' initial response to my question when I asked about dry cleaning:
"I would not dry clean.  Just pop them in a washing machine inside out at 30C (about 90F) and perform a gentle wash with any detergent you have lying around.  Spin at 400rpm, do not tumble, then un-inside out them, shake well to remove any creases and leave to dry."

There is no way to control the speed of the spin on the washing machine I use (nor is there on professional machines I have used at laundromats). There is just a set spin cycle. And as far as the temperature of the water, I have the options of cold warm and hot. I'm guessing "warm" on that? Do some of you have washers where you can be that specific about the spin and temperature? I've never seen one like that before personally.

So here is my biggest concern:
Because of the rigid nature of the jeans, creases might form on the jeans in the washing process and discoloration would form along these creases. This has happened to me when I have washed deadstock Levi's 517 and 646 jeans prior to wearing (and yes, they were turned inside out). And these Iron Hearts (21 oz), even with the good amount of wear they have, are obviously stiffer than those Levi's.

The washing machine where I live is not the type that fills up a tub of water and shakes everything around. It's is one of those High Efficiency washers, and it washes with a minimal amount of water in a horizontal (top loading) direction. When I recently washed a new pair of regular Levi's in there (after having warn them for a while), they faded slightly on one leg (the side they were facing down) and less so on the other. That is to say, one leg came out slightly lighter than the other. The situation somewhat resolved when I later took them to a dry cleaner, and they look a bit more even now.

At my local laundromat. They have front-loading, vertical washing machines, so maybe that might be better, but I'm not sure. But still, I have gotten creases on 517s and 646s in front-load style washers.

So as you can see, I have a lot of concerns here and don't want to ruin my jeans that I have invested not only money into, but also a lot of time wearing them in nicely.

For these reasons, I thought a dry cleaner might be the most stress free option, and it's only a few bucks. But then I noticed that on the inside of the jeans, on the pocket, it says "no dry clean." And Giles said not to dry clean, without offering explanation.

Will dry cleaning them damage them? If not, it would be such an easier solution for me. And I wouldn't have to worry about any shrinkage, either, since I'm pretty sure they're not sanforized.

(And hand-washing would be difficult to accomplish in my apartment, though not impossible. But it would require a ton more effort that dry cleaning.)

Please if anyone can explain why dry cleaning them is unwise, I would be greatly indebted.

Thanks,
Felix