The EF 135mm f/2 L has been on my buy list for a couple of years now. However, every time I get the money saved up to buy it, I end up buying something else.

Sigma 35mm f/1.4, Canon EF 85mm f/1.2 II, Canon 5D Mark III...

One thing that keeps me from picking up the 135L is that it doesn't replace anything in my camera bag - and I have no spare room in the bag. If I were to pick up the 135L and take it on a shoot, I'd have to leave something else at home.

Dilemmas, dilemmas...

:-)