The more you purify your cactus drink (blended and boiled, blended boiled and filtered, blended boiled filtered evaporated, ethanol extraction, ethanol extraction with evaporation of leftover alcohol, acid/base extract or cielo tek, synthetic mescaline) the less plant matter and mucus you end up consuming in your final preparation. The less mucus means less for your stomach to digest while also incurring the loss of some secondary and tertiary alkaloids present in whole cactus. For some, this is highly desirable and can help reduce some of the GI discomfort that comes from consuming 100gs of cactus. Others indicate that the more purified your product is, the more you move away from a traditional experience. There's no one right path here. I can say from experience that synthetic mescaline can be a very different experience than alkaloid extractions or straight up tea. I've had wonderful experience with a number of varieties (a/b extracted powder, ethanol extract, cactus tea, synthetic mescaline, and a combination of synthetic mescaline and a/b extract powders). All have provided me with a worthwhile experience and all have had different characteristics trip to trip. Mescaline is by far the psychedelic I feel the most personally connected with as I have been growing San Pedro and T. Bridgesii now for 25 years. For reference, I live in the NE US and while I have to be mindful of the seasons, overall I've been able to have a variety of healthy and happy cacti over the years, some of which I've prepared and consumed but most of which stay simply as plants that I have in my life.
Vomiting can be a component of the trip regardless of form. I find that most mescaline has the potential for nausea that gradually comes on and becomes increasingly prevalent over the first hour. The worst thing to do is to fight it - prepare yourself to stay somewhere near a toilet and washroom until you've cleared the first couple of hours as you don't want to be somewhere struggling to keep it down. In general, whenever I have experienced nausea, it immediately resolves once I've thrown up and there is no unpleasant feelings after that. Some believe that purging is part of the healing process as it expels toxicity in the process. Ayahuasca has a similar belief attached to it and may be rooted in actual medical benefits - these plant medicines were used to treat a variety of ailments and purging can help eliminate amoeba/protozoa that can be found in drinking water in hot climates. Expelling these organisms by vomiting/diarrhea can help the sufferer's health improve whether through a biological or spiritual cleanse.
It's unique compared to LSD and mushrooms - I find the trip to be very visual and also very clear headed. The emotional effects are quite powerful, and its capacity to help us face traumatic experiences is significant. There is a lot of work that goes into the trip (be it the cost to produce, procure, and obviously to consume) and that also makes it a special experience. It is also pretty unique in that the effects wax and wane throughout the 8-12+ - where one might find themselves feeling very close to sober for a time and then experience powerful and profound hallucinatory experiences. It's very much its own trip and very worth exploring IMHO.
