I say it was an impulse buy but I did think about it for a week before I took the plunge. Sadly in that week they sold out of my preferred size within the first week of it being up on the site. Reluctantly I got the next size down.
Amazingly it fits! Apart from a couple of sleeve-length related issues - which probably would have happened if I had bought the bigger size too as I have exceedingly long arms, to go with my long legs and even longer body.