oooh- I have to chime in (late as I am) and say the sweetleaf grape stevia is amazing. Added to lemon water it's 'I-can't-believe-it's-not-Kool-Aid'.

I do usually notice the taste with stevia- however some flavours mask it better, and sometimes if you use a little, then supplement it with another sweetener in small doses (eg xylitol) you get the sweet without the bitter taste.

I'm planning on buying the lemon stevia- for lemonade. I use the vanilla creme or chocolate raspberry with a little xylitol in my cafe mochas, my co-worker loves the english toffee in her tea, my mom and bro use the chocolate raspberry in plain yogurt, I use the apricot with either cucumber or lime water...

You do have to use small amounts, and I won't argue it can be a bit of an acquired taste- but I consider it the more natural of non-caloric no carb sweeteners to use.