When it comes to travel.... at least by air.... I go cheap on my brush. I don't want my Vulfix going to Chicago when I'm headed to Atlanta.
I'm going on an extended trip this spring... to Australia... and my travel brush of choice is the $6 BurmaShave Boar Bristle from Walmart. This brush is pretty stiff but works fine with soaps. It will be accompanied by a no-name German knockoff of a Gillette Tech travel razor and a small container of cheapo Classic Almond soap. If this shaving travel kit is lost... no tears will be shed. But I can still get a decent if not decadent shave every day.
Merkur: Slant, Classic, HD
Gillette Tech: W2 Bakelite, Ranger, Thick Handle, English Ball Tip
Gillette: E1 / E2 Fat Boys, B3 Red Tip, Old Type, O1 Black Beauty, L4 Blue Star
Blade: Derby, Dollar General (Israeli), Swedish Gillette
Soap : Honeybee Spa, D.R. Harris
Brush: Vulfix Pure Badger #849