IIRC, the first one posted, (320MM) should aproximate a straight rate spring comperable with the stock setup, but will probably bottom easier, since the stock springs are progressive. The 2nd (340MM) should be a decent upgrade on the stock springs. That being said, there is no way to tell what kind of damping curves to expect. A piece of good information is missing. It would be good to know what diameter the shaft is on the cylinder. Looks to be about 10MM, but my calibrated eyeball ain't what it used to be. 12-13MM is a good size for the rod nowadays, but in tandem, if made correctly, that should work. Probably from China (surprise). No mention of a warranty. They look pretty good, and probably will beat a set of thrashed stock boingers. For the money, I'd say they are as good a "chance" as anything else cheap. Buyer beware, and please, tell us how they work out.