Used to be I only did WineXpert. Lately have tried a bunch of the Paklab kits when they are on sale on Amazon. Have recently tried 2 RJ Spagnols (Grand Cru and Winery Series), seem to be going well. Have found myself looking at the mid tier Cellar Crafts with smaller grape packs lately and may try a couple of those this summer.
I buy from a lot of different companies - but at the moment it seems to be RJ that I am buying more of. It was Vineco - I like the Cheeky Monkey series and the Cellar Craft reds with the grape packs at a reasonable price. But as I make more wines - I am making more reds and a little higher priced so I am buying more Winery Series and EP from Spagnols.
Winexperts australian shiraz turned out great. Right now I have RJS EP Cabernet in the carboy and it looks wonderful.. tasted great too. Looking at doing and eclipse (we) and another EP, maybe a merlot or another shiraz