I just got a set of the ones I have featured on the Welcome Page and also ordered mainsheet to go with it. I had the supplier remove some of the cover from the core, so only the core runs through the blocks.
When you ease it, it really releases -- I remember that my old blocks have managed to give me problems in the past. In light air I would do a roll tack, release a little mainsheet.., but alas, the sheet would not go out and the boat would go in to irons or slow way down through the turn. With the new setup, there is no such thing happening.
Also, when sailing along and a puff hits it is a snap to ease the mainsheet a bit and keep on hauling.
No more snapping and tugging, snapping and tugging.
Rick