I've used the lump for a few cooks. My experience is that it gives off a lot of heat, smells terrific, very little ash, burn times a little shorter than I expected, and like most lump I've used, there are some oversized chunks in the bag that need to be broken up in order to properly pack the charcoal ring or spread the coals out in my Weber kettle.
I like it a lot and would continue to use it except for the fact that the place I bought it is now out of business!
Pat