I have an er86 on my 103 and it is definitely worth the money.
I went through the whole stock clutch bs and eventually had to ditch it.
I never used the er2 clutch pulley but this one is very nice.
Out of the box the clutch pads have full contact with the bell and the ability to adjust the spring tension without taking anything apart is great.
The clutch bell is machined and there is almost no slop anywhere .
It has held up great so far, set up to engage around 7000 rpm when my pipe starts to hit.