There are several posts on here from people who use different methods.
I always drill them out using a titanium drill, used to use the bullitt type of drill but you would be lucky to drill three bolts out with one of those before they were knackered. The titanium drills last for ages.
I have got a colour gaz blow lamp (B&Q) heat up the spider around the Torx bolts then use torx socket, this works most of the time have used angle grinder on the ones it did not work on.
Bernie
yes the heat treetment does work 🙂 also tighten it 1st helps and a good wack with a lump hammer can loosen it up, and a good quality torx bit…
broken hundreds of the cheap ones 😡