Not all bikes will take an offset bushing- if the clearances are tight then the reduced minimum shock length can cause fouling, so be careful- it’s essentially the same as fitting a shorter shock. (also, with some designs with clever linkages remember you’re putting the startpoint of travel in a different place. Not going to affect a Heckler obv)
I got the Steamer Industries ones, they wore very fast unfortunately- the hole is very close to the side of the bushing and that seems to make it keen to ovalise. Others are available and might be better.
Works headset is nicely tried and tested though, very pleased with both of mine.