I've found PC-TEA to give me results that seem to me identical to what I was getting with xtol. Since I wasn't using xtol very frequently that's what I switched to. PC-TEA seems to keep for ages. I had xtol fail in the past but it seems that issue has been addressed. It happened a number of times and I just didn't feel I could count on it. Glad to hear others find it so reliable.