I've gigged quite a bit with my Four10, and lately I've taken my Big Twin II out a couple of times and really like that too. Neither one is lacking in volume, even outdoors. The Four10 cuts through a bit more because it's more mid-focused, but the BTII sounds bigger and is a bit more textured because of the extended highs. The Four10 has a lot of personality, so it can make a bland amp sound better. The BTII is more honest, so a bland amp sounds a bit bland, and an amp with great personality (like my Reiner VHF700) really shines.