I tried Sera salt and it was very inconsistent. After my tank was tossed into whack and several hundred dollars spent in water changes to TMRP I never even considered spending my money on Sera's expensive test kit's.
I will stick with Salifert kits. I am thinking of trying Elos though...
Billy is one of my best buddies and I have him on a role on kits and salt mixes testing on our RC chem forum. He will be doing more on these. This was his first one, so it is kinda watered-down. I'm trying to get him to expand more in his articles.