A normal prime for landscape?

I'm weighing up whether to pickup a wide prime(the Canon 28mm 1.8 and Sigma 30mm 1.4 being at the top of the list) for my 550D to get a normal view at the moment and just wondered whether anything has expereince using them for landscape work.

Low light people shooting and perhaps some street photography is part of why I'm looking to pick one up but honestly I'm not sure i'll get enough use out of it doing that to justify £300+. Landscape makes up most of what I shoot and I'm just wondering whether it would be much use there, espeically for shallow DOF work compaired to my 15-85 and 10-22.