I'm happy with mine.
Considering your just getting started and may find in a year or so that you don't care much for casting or that in a couple hours you can turn out enough boolits to last you a couple years, the 4-20 should do you just fine.
I have one, but I can not get good fill out on the heavier bullets. I use a magnum melter with a ladle for those.
I've often wondered why some people can pour heavy bullets with a bottom pour mold and others can't? Obviously somebody is doing something different but what? I'm on the bottom pour side.