Well, I have read a lot of good things about it, especially 4-5 years ago when it was really popular. I have even used it with great success as a calcium/d3 source for lizards that received no natural sunlight. It worked fine for me then, so it ain't all bad. But, in trying to compare it to reptivite, they are two different types of supplements. Miner-all is meant to be a calcium/d3 source, whereas the reptivite is a multi-vitamin that provides a number of different vitamins. You would use it to replace something like RepCal, not your multi-vitamin supplement.