I had a DKM heavy duty single mass to go with my turbo install. The DKM quality is good but the heavier one for more power has far to much peddle pressure. I would not recommend it for a daily driver or anyone without a very strong left leg. They do make a stock replacement that has a standard peddle pressure. I will be doing a six speed gearbox swap soon and have a twin disc unit that I will be installing and I cant wait to get a more stock peddle feel.
It all depends on what you what from it. Pretty much any good quality clutch will be more then most people need.
Personally with the straight six I don't mind a lightened flywheel. There was very little additional vibration as the six is very balanced. But then I also changed to stiff engine mounts and everything else later. Mine and my misses car came from the factory as identical 2.8s but they ware worlds apart now. Hers is a comfortable to drive where mine is more thuggish.
The DKM item was quite a bit more ££ if I recall correct.
I really wanted to get a lightweight clutch but after speaking with RTS who do a load of LWF for FWD cars said that don’t offer them for this engine, not because of engine smoothness side of things but rather the gearbox and diff. Something about them taking extra strain or such, can’t recall exactly.
and I think it was half the price of the cheapest DKM and the budget was already blown twice by that stage