Hi Needle
I have put 22,000 K on this stack .
I have not measured it lately but it still has plenty of height left and the friction zone is still really wide.
It has rattle but not as much as before.
I pull the stack out regularly clean it with brake disk/clutch plate spray cleaner and rough up and glazed friction plates.
Really easy to remove the plates 5 min job , I made a simple tool a piece of steel wire bent into a U shape with 2mm right angle
inward facing hooks too grab the plates .
Have a go , pull your stack out and inspect , clean and re stack swapping friction plates if some are worn more than others
If you have a spare steel plate throw one in it will increase your stack height and give you a longer friction zone.
I always keep a few in the shed.
The Barnnett is way cheaper but can give friction zone groan on take off if left dusty or glazed.
The pro cutter basket compared to the OEM which was flogged to death with 1-2mm divots has held up really well.
A steel basket would probably last for the life of the bike but I recon would be louder.
Gowanlocks don't sell Surflex plates anymore they sell their own manufactured plates less than Surflex but more than Barrnett
but you can purchase just the friction plates and re use your old steel plates.
Dez