My suggestion was more meant to address mrfish's symptoms than kulivontot's.

I switch between wheels with SRAM/Dura Ace cassettes and my climbing wheels with the Recon cassette. At first I had no problems. Shifting wasn't quite as snappy with the Recon but certainly good enough. As I put a couple of years on the bike I began having difficulty getting the Recon to shift well across the entire range (as described by others). The Sram/Dura Ace cassettes continued to shift accurately. I changed out the I-Link cables and housings due to normal wear for a set of Shimano Yumeya cables and housings. The shifting with the Recon is now better than ever, and almost indistinguishable from the Sram/Dura Ace cassettes. I think the bottom line is that the Recon cassette is intolerant of any excess friction or slop in your system. I also us a Park tool to make sure the derailleur hanger is aligned. You'd be surprised how easy it is to accidentally bend an alloy hanger. Use the Recon as a race day only cassette and it will last a long time.

Thanks for the inputs. I added a new cable and i-link inners, and have the correct spacers, so that should not be an issue. I will get the local shop to check the hanger alignment.