Get the 6 cavity LEE. You will find that culling the losers from an hours worth of casting from the 6 banger production will still leave you with hundreds of usable boolits, whereas the two-holer will leave an appreciably smaller number to use after you pick out the baddies. And there will be baddies.
With the 6 banger, start by pre-heating the mold, either on top of your pot or on a cheapie hot plate, Then, when you start fill only the first cavity farthest from the sprue handle, do that twice, then fill the two farthest and do that twice. Ignore the boolits, just fill and cast at a comfortable rate, allowing the sprue to just freeze before you cut and dump. Continue to fill the mold, increasing the number of cavities every other cast, until you are running on all 6. Then go to town, place an ingot or two on top of the pot to preheat and then you can prolong the sweet-spot production by adding more lead to the pot without having to pause and wait for the temperature to recover. You will easily make a year's worth of boolits in an afternoon, with time left for mowing a small lawn. {At least if you only plan on shooting 500 rounds a year.}
I tend to roll my eyes at some of the claims of casting excellence, with flawless boolits raining endlessly from their chosen molds. Well, sometimes it does happen that way. I have a 4 cavity 358-311 that casts like that, but I have about 100 others that don't and a couple that are just evil. Don't get discouraged if you have a few hickups, come on back and pick our brains. There are probably 10,000 years plus worth of collective experience here, somebody will have an answer.