The unflavored is not bad. I started with it in fact. It is very smooth--and a bit tingly.... due to the active fermentation. It continues in your frig... In fact when I called them once the gal on the other end chuckled thinking I was calling to complain.
She said people "forget" it in the frig and when it goes past the sale date, it ferments and expands the bottle and may burst!
Ours never lasts that long. Usually they have 2+ months on the date when we get ours.

Gluten free and lactose free. I think it feels nice going down too.
That is something yogurt doesn't do for me.
I started at 4 oz a serving. I still don't drink large amounts at a time as it is acidic. Right now Kroger's added cherry to its offerings and I like that one even better than the peach. Shake it really well before each serving. It is not expensive IMO.