Hey Inkbandit,
I've used the 'MEGA bolt in' type fuses and although I havnt had a chance to use the solar panels to charge yet (was to lazy to wire it in on my offshift), charging with the crank battery while driving hasn't cause me any problems, I did however check the modules temperature with a infrared heat gun, and it was around 55degree's while parked after a long drive and engine still running, which Redarc says anything over 50degree's will cause a less efficiant charge, but thats about it, damn glad I spent the extra money and bought a good product... If anything happens though I will look to seek the breaker option.
What battery monitoring systems are you wiring into the vehicles you install the bcdc on. I have yet to install one, and to be honest, probably wont...
Cheers,
Shaun