You win the loaded question of the day award!!!
You probably need to try a couple different ones and choose your favorite. They all have pros and cons and different people like them for different reasons.
Here's my experience: I've used Calhoun, Polyone and MF (never tried LC). Of the 3 I prefer MF even though it's the most expensive. I know Robert and Jeff (it's a family business) and they take good care of their customers. I believe the plastic is higher quality, has more stabilizer in it, smells less, works really well in a pot or microwave and I don't believe it has any heavy metals in it. It is extremely clear and in my opinion easier to work with (more forgiving) than the others I've used. The other great quality it has is it doesn't settle / separate like some plastics do. You can literally leave it sit for several months and not have to shake it - big bonus if it's a 5 gallon bucket!
With that said, it works for me (that's why we sell it). We only sell it by the pint and quart, I don't sell the larger sizes because you can buy it directly from them for the same price as I can buy it, even if I buy it in bulk 55 gallon drums. They have better shipping rates than I do so it just doesn't make sense for us to carry it. I normally buy the 5 gallon jugs for personal use and to test the molds with.
As I said above, try a few and see what you like the best based on how you work.
Tight lines,
Jason