OMG I FOUND IT!!! Temporarily out of stock!!!! Darnit!!!

Ok, so long story short there's this bathrobe I had for like 6 or 7 years (maybe more) that my sister got me from Macy's yeaaaaaaaaars ago.

My question is, I'm a medium, 5' 10". For bathrobes, would you go with medium OR would you size up to large? The medium fit me perfectly, but I hear people keep saying you want to size up regardless.

What's your opinion on it?

Thanks.