Matt here,
Not a thread person, but wish to contribute. First pair of Iron Heart jeans and I'm a big fan. First pair of selvedge denim too.

I want to give my feedback on these jeans.  I'll say up front; a fantastic pair of pants, company out of the UK has been great with first-class customer service.  I intend to buy from them again.

Purchased in July. Sent back for hemming. Probably my only gripe, I was surprised that the hemming wasn't done with overdyed thread. That was the point of sending it back (from the US).  I should've been clear but just assumed they'd match the thread. First world problems!

Worn probably 75-100 days. Oddly, about half-way they developed a bit of a mild and inoffensive smell which I read here was a possibility with the over-dyed? But then IH modified their process? Oh well, then the smell went away on it’s own without a wash.

Just washed first time yesterday, by hand, denim detergent, 40deg, bathtub, 30-min soak, hang dry.

The 14oz is (to me) quite substantial. I can't imagine the 21oz. (though I guess you could say I'm 21oz curious?)  I am glad I opted for 14.  It's NOT "lightweight" at all and after at least 75 days wear + wash, they are hardly showing any wear at all.

I would say a small amount of dye/indigo came out in the wash.  They went from basically black to extremely dark blue in full Colorado sunlight with fading along the edges of the pockets, fly and rear belt loop, corners of pockets. Mild whiskering and honeycombing only. I wouldn't say there was any "shrinkage" only what I'd describe as a slight “tightening-up”. Nothing major. Likely return to normal after a day or two.

I think really "breaking these pants in" will take a couple hundred wears.  I don't think they will "soften up" easily.  They will take wear & tear well.  They won't fade quickly unless you're wearing them for hard manual work daily. I will double my efforts!

I will say the 777s fit me perfectly.  I was a Nudie Grim Tim fan and these fit better, 30in waist fits perfectly.