My synthetic of choice is the 24 mm AP Shave Co. SynBad. I find this knot suits my lathering style the best of any synthetic I’ve tried (but it won‘t replace any of my badgers or boars when I’m at home). I carry it in a plastic prescription pill container with holes drilled in the top which cost me nothing thanks to my local pharmacist. I too don’t believe in downsizing my shaving and other grooming kit when I travel and the SynBad is right in my sweet spot for a shaving brush in terms of size; the only grooming item I have down sized is my aftershave splash which I carry in a 50 ml bottle so that it easily fits into the prescribed clear plastic bag for liquids, creams and gels needed to carry on an airplane.That’s what I do. I don’t use synthetics at home, but their quick drying property wins me over when it comes to travel. On my last trip I took a badger with me, but regretted it when I had to pull out a dank brush for each morning’s shave.

)