Review on Parts Express Electronic Solder Diameter by Marcus Freeman

Works pretty well and is much easier to work with than lead-free solder. Since I soldered the 18650 lithium cells together, the lead content didn't bother me (I also cast my own balls, so lead doesn't bother me). It seems to work very well, the only complaint is the price, but the can itself is currently $20 a pound so the price is about what it should be.