Seachem's are nice. The ph test uses a slide card to determine the corresponding ph value and the ca and mag kits use syringes and you just calculate the # of ml's needed for the color to change. Of course La motte would be the best and most expensive.

Still don't understand why people complain about api's kits. Sure, they're only good for getting you a range, but they are pretty accurate. I know the NO3 kit shows similar values above 10ppm compared to my salifert kit. But, of course anything below that and those 5ppm and 10ppm beige colors are pretty similar.