I've just had a new clutch fitted to mine and had the AP unit fitted following a chat with my local TVR garage. Lots of discussion on Helix on the T350 FB group.
I've had a helix in my t350 for 3 years now and zero problems. That said I think I'm more one of the lucky ones from what I've heard. If anything dies go wrong with it I'll likely switch back to AP.
Is this helix clutch the 'second' option you can get via the official TVR parts outfit, which is advertised as fully rebuildable, improved design etc. etc. ??