Looking at the ingredient profile here, you'd be better off just buying these as a standalone as opposed to having them all jammed into one pill. Your quality is going to be much better and you can control your inputs more efficiently, not to mention it's going to be more cost effective in the long run buying them separately.
Personally I don't think the caffeine to theanine ratio is correct here. For best results concerning that I've found it is better to dose 1:4, caffeine to theanine.