I've only used the solid because I couldn't find the paste. I think the paste would probably work out better but the solid has been fine for my 5 years of building. The problem with the solid is when you get near the end of it's life, large chunks fall out. It's very much like candle wax.
The way I applied it most of the time is just drill into before drilling into the metal. Sometimes I'd rub it on the bit as well.