It does sell-out, the Glampink and ready made tents sell-out quickly. Day tickets do as well. But GA weekend tickets tend to be ok until few weeks before.
I always liked Travis first album - Good Feeling, It did not make much of an impact but I think its potentially there best work (IMO) though in terms of putting them on a big stage its not the well know content.
I think basically all Travis - Well known songs came of the 2nd and 3rd albums -