If your a bit Ham fisted, buy yourself a Torque wrench. Have a look at this Snap on set:
www.ebay.com.au/itm/Torx-3-8-Drive-Set-Snap-On-T8-T55-12Pc-NEW-Philips-Screwdriver-/280901433793
yep i too have snapped a few torx went and bought a high tensile genius+ brand T45 $16.50 a pop but will be replaced if broken lifetime warranty from nut and bolt shop good luck
Broke a Blue point torx T45 yesterday removing rear disk bolts on my 07. There I was stuck, Saturday arvo,with bike bike apart, no reputable shops open, so had to buy what I could from a Supercheap shop,
Torx key set was made of cheese, whole set now resides in the bin along side the other 4 removed brake rotor bolts.
Ended up drilling and easy outing the rogue bolt. I have never srewed a torx bolt back into one of my HD's except if they are machined bolts like the rear brake pins etc
Generally replace he torx with cap heads.
If ya can get hold of one of these Snap-On Cycleset tool kits you'll appreciate it.
Got everything for the road trip as well as being excellent quality for use in the workshop.
www.ebay.com/itm/Motorcycle-tool-kit-snap-on-/200772366411#vi-desc
You have expensive tastes Rider, 20 hours to go US $182.50 + $15.00 Postage...Must be Gold Plated
Absolute bargain,,, last time I checked they retailed for about AU$650.00 from the local Snap-On dealer in OZ !!!
If the screw/torx head is tight enough to snap the tools then you need to shock the item loose first. This is how to shock the item loose.
use a brass punch of healthy diameter say 1/2 inch min. Firmly hold onto the head of the srew or bolt then give it a FIRM whack with a hammer (the punch not your thumb). The brass wont damage or mar the head of the screw bolt and I guarantee that it will be easier to undo. If you have the ability to strike the srew or bolt directly (if they are to be replaced) then this will work even better.
Dont be afraid to apply a decent amount of force with the hammer and brass punch. IT WILL HELP.
Regards
P.S. I've been a fitter for over 20 yrs, this works.
I use torx bits a lot, snap on is the only one to buy if u dont want problems .
Snapped 2 Kinchrome Allens trying to remove rear disc.( had a cheater bar on them and could feel them flexing so lot of pressure applied) . Ended up buying a manual impact driver to un freeze them.They just dont make em like they used to i guess. Have a half inch drive sidchrome socket set that i have had for 30 years ,cant seem to break it , new sidchrome breaks when it rolls off the work bench for me