I've used machine grease for 40 years or so, and find it better than most commercial bullet lube - cheaper too.
If you seat your bullet on the bottom driving band, apply the grease with your fingers, seat to full depth and wipe off the excess, you get cleaner reloads than with tumble lube, no powder contamination, and it is not much - if any - more effort. You don't need a lubrisizer either - the lee sizer works very well.
On my bench at the moment, I have Canadian Tire Moly Grease and Chevron Duralith; Both work well for me, perhaps a slight edge for the moly at high velocity( up to 2500 or so).
Best of luck!