Well for the gut issues DMPS or DMSA capsules seem to be very good. I've done chelation for more than 3.5 years and have few issues left (focus is in the jaw bone area, not surprisingly), but whenever I go on a DMSA Cutler round (for 10-14 days, 100mg DMSA capsules and 200mg ALA every 3 hours) my stool goes from "quite good/okay" to "very good" during the round. That's why I conclude that for the gut chelator in capsules is good. While for the rest of the body the problem is that only 10-20% of the chelator makes it into the blood stream this could be just what the gut needs.
By the way, I also concluded (by personal long-term experiment) that Candida issues during/after chelation are not related to the chelator (it is claimed DMSA supports Candida growth directly), but to mobilized heavy metals that end up in the gut. Proof: I take more DMSA than ever, and directly into the gut (I used to do DMPS infusions mostly), but have less gut issues (like bloat) than ever before. If DMSA were directly to blame for Candida growth that could hardly be the case, so I DE CLARE it (just another) urban legend (about chelators).