Something to consider, when choosing a shock, is if the shock was designed to be used with a linkage. I bolted a CBR 600 swingarm on a FT 500 single years ago, and eliminated the linkage. Without the progressive stiffening provided by the linkage, the shock would bottom easily, even though it felt fine for the first couple inches of travel. Put me on my ass the first time I chucked it into a fast corner.
I switched to a shock from a Hawk [the V twin, single sided swingarm model]. That bike has no linkage, progressive dampening/springing is designed into the shock.
Might save someone a painful lesson.