Nomattic, I've done 14 liver flushes, with #15 coming up this weekend, and I've yet to do a single enema or colonic ... I'm seeking "natural" health, and dang if I find anything natural about either!!! You must make sure that your bowels are in good working order. If you are constipated, under NO circumstances ever do a liver flush, the toxins have to be able to be released quickly or they recirculate and make you feel awful!!!!
Like yourself, I prefer herbal products and use The Barefoot Herbalist's cleanses and herbs from the Ask Barefoot forum here.