Received very quickly from Marketplace seller. This is a nice quality heavyweight T-shirt which should wear well and be slow to go out of shape. Having said that, though I love it and rate it 5 stars for me personally, since I am a slim-ish female (size 12) suspect this shirt is cut a little on the snug side for male purchasers. I bought a medium, and it is a loose but not baggy fit on me.
Advizable I think to take the 38" - 40" measurement as an exact fit, if you are between these two chest sizes the shirt will be close fitting.
Which is precisely why I bought the men's - I wanted loose fit. Delighted to find that it does fit me the way I wanted, but if you are a guy you might consider purchasing a size larger than your usual if you don't want it too snug.
Edited following later purchase - I have now also bought the yellow version, in commemoration of Bradley Wiggins's 2012 TdF victory. Was slightly concerned because the shade of yellow depicted on this shirt's purchase page was rather more of a pale lemon than a true TdF 'Yellow Jersey' yellow. However, when I received the shirt I was pleasantly surprised - the shade you see on the screen is an example of colour representation failure, this shirt *really is* in proper Tour de France 'Yellow Jersey' Yellow, so if that is what you want, go for it.
And in case anyone is wondering, many months on, my original purchase - the black version - has indeed worn well and has not gone out of shape at all.