I prefer the travel size than the regular ones because I love doing my makeup closer to the mirror. It's shorter, easier to handle and compact. I'm wearing glasses, so when I'm putting on my makeup I'm partially blind.
I'd love to get the coloured brushes - aqua, purple, coral, mrs bunny blue & pink but I'll stick with the classic black to match my other brushes.
UPDATE (8th March 2013)
I just placed my order for Sigma brushes from Luxola today. I'm happy that they have 20% discount in conjunction with today's Woman's International Day. Yayy can't wait for them to arrive! :D