'pure cotton' and '100% pure cotton' is a material difference, and can go to cost, as well. (At the risk of sounding banal, or snooty, but that's not my intention, I promise.)
Some labels will say Pure Cotton -- that is a reference that the cotton in the shirt is pure cotton, but it could still be a blend of pure cotton and any number of other materials. A '100% pure cotton' shirt means, well, that.
Also, Thomas Mason has a couple of lines of cotton - their standard line, Silverline, Goldline, a 'bespoke line' for P Johnson, and cotton they use for J Crew shirts.The grade of the cotton within the same mill factor into the cost, as well. Each shirt (made from Thomas Mason cotton) by different makers costs different.
Before we start splitting hairs: if I had to choose between the shirts, I'd let the workmanship and finish be the deciding factors. And as a tie-breaker, I'd go with whichever cotton felt nicer, personally, against my skin.
Thanks for the informative post Nabilmust - appreciate it. Also good to know your daily wearers are TM fabrics Romp, that is very reassuring. I think I'll try out a Cottonwork Thomas Mason in a shade of blue w. button cuff and see how I go with that, and then decide whether I want to pull the trigger on any more from there. Anyone know if Cottonwork has promos or discount codes? I have a 5% off coupon I got with my fabric samples, but was hoping someone here might know of a better code ;).
Aside from that, to those who have been buying cord pants (think Prof B Bear had some Landsend purchases recently), what shirts would you pair with 'em? I'm thinking OCBDs in (don't slay me please) white or blue, with a sweater over the top (e.g. one of Bears previously linked fair isles, or a cable variety). Or perhaps a chambray pinkish/red or blue sort of shirt might work as well? I think that would that be a good fall/winter weekend sort of look. I'm also a bit confused as to what sort of shoes to pair with cords.