i asked helix what they reckoned about their clutch, they said:
These drive plates are 7.7mm thick when new. We advise that you have it repadded once they get to about 6.6mm thick.
A repad of a 4 paddle plate costs £44.98 + VAT. Carriage is £8.50 + VAT (Next day delivery service with City Link). We usually complete the work within one or two days of receipt of the plate.
Helix Autosport Ltd
so i measured it and its 7.4mm across the thickness, so great, barely used!, no need for getting it re-lined yet. al did say it was only used for a couple of races or summat.