I use a BernzoMatic BZ4500HS. It’s identical to the Sansaire torch (except for the colour and the lack of an over-inflated price). The BZ4500HS has a wider flame than the TS8000, so it works better for searing.
For gas, I’m using MAP/Pro (propylene), mainly because it burns a bit hotter than propane or butane. It’s also what is recommended by Modernist Cuisine at Home. (Good book, BTW, if you want to try some fancy and technical kind of cooking.)