Hey all, I'm putting in a sub-panel tonight so I can run a few more circuits to the kitchen. I bought a SquareD QO panel that says it can hold 6-12 circuits. Now, I count 8 slots in the panel, but realize they want 2 left open for some reason. Question is, are there any drawbacks to using tandem breakers? These are the half-size breakers molded into the same "shell", and only take up 1 space. They make sense, but I just don't know what the negatives are...if any. Anyway, thanks for any info!