Now that I've used the V2 version of Mühle's silvertip fiber brushes, I would highly recommend that you try your best to verify the STF version. If it's V1, I would pass on it. V2 is simply that good. I doubt the travel brush is V2.
I own one of those. It is very convenient for travel, dries fast even inside the tube. The knot is differently shaped than the ordinary Muhle Silvertip fibre, the loft feels higher and the backbone is more pronounced. It feels remarkably different compared to the ordinary Silvertip Fibre of which I have two (21 and 19 mm).I just came across this Muhle travel brush. The knot is 21 mm knot. I was considering a Muhle synthetic as a travel brush and wonder if any of you have any experience with this one.