In case this is of any interest:
Heco HD Drive, Spax T-Star plus (2x), Wuerth AW (2x) and Wuerth RW all sized “20” - the one above all, a little out of focus is a regular Torx 20 - and that is the common denominator.
And the corresponding fasteners.
Wuerth Assy 4.0 (RW), Wuerth Assy 3.0 (AW), Spax T-Star plus, Heco Topix Plus (HD Drive)
All of these can be driven with a regular Torx 20 bit if you must, albeit being proprietary drive/ head designs.
Two standing out are the Heco HD Drive & Wuerth RW drive, as those form a truly rock solid connection between correct/proprietary bit and fastener when pushed on. This allows for precise, one handed operation without magnetized bit holders, or sleeved bit holders. Obviously that wears over time, but it’s god sent in some situations.
The Heco HD bits are furthermore “reverse” compatible with regular Torx drives.
I used to be heavily invested in Spax fasteners, but after trying Heco’s Topix Plus & Wuerth’s Assy 4.0 fasteners I haven’t stocked up on any Spax T-Star plus fasteners in ages and I’m phasing those out/ replacing them with Heco and Wuerth. Between those two, it’s just a matter of which supplier I have an order going with. Depending on the task I still buy from other brands as well, as not every configuration of fastener is always available, but that is very seldom.
When looking at this, consider the difference between HD drive/RW drive to regular Torx drive being an equally whole landslide type difference that Philips/Pozi to Torx has been before these.
Wuerth AW drive in comparison to regular Torx was never that impressive.
Spax T-Star drive has been solid in regards to positive engagement/ cam out - but never formed that much of a rock solid connection between T-Star plus bit and T-Star plus fastener.
Kind regards,
Olli