Hi David.
Your 60w solar panels should have a max current rating of around 3A a panel, as the working voltage for the power calculation is somewere around 20v not 12v. Most solar panels of reputable manufacture do put out there rated output. Also MPPT controlers do not boost the power out put from the solar panel, as this would be imposible unless it had an aditional power source from else were. MPPT controlers have the edge over PWM controlers only in marginal operating conditions and in full sun light there is no real difference between the two.
Probarbly of more importance is fitting blocking diodes for situations were multiple panels are conected in parallel to a single regulator and shading will occur on one or more of the panels ,like what tends to happen on a boat.
Kind regards
Andrew.
