I've tried making shrub before. It was probably just a bad recipe, but I found the vinegar character to be just too overpowering, burning my throat, so I dumped it. And I like vinegar a lot, on salads or for dipping bread into, etc. It might just be more a matter of finding the right ratio of vinegar to fruit juice. Perhaps just 5-10% vinegar is all that's appropriate. I don't know much more about shrubs.
Now kombucha, on the other hand.... I just made my first kombucha, and damn, it turned out just perfectly wonderful on my very first try. Took 13 days to get to just the right amount of vinegar where you can taste it without getting burned. Currently in bottles. Popped the first bottle a few days ago and it wasn't carbonated yet, so I'll open the next one in another couple days. But it was so easy. The only downside really is the time involved.... 13 days to ferment, then another 7? 10? days to carbonate. I'll know more soon.