I have a free solar panel simulator available at
http://Yachtsoftware.org that may answer some of your questions. For example with two 120 watt Kyocera panels pointed directly at the sun full time you would get 32% more amps in June in Baltimore than if the panels were simply fixed mounted on top of a bimini. That is a lot of work in manual alignment for a not so impressive improvement in output power.
The program also shows tables of expected amps at all times of the day including the morning and evening for both a user specified fixed mounting angle and a perfectly aligned with the sun panel. For Baltimore in June with a simple PWM controller charging a depleted battery:
Mounted Aligned
Time on Bimini With Sun
5:12 AM 0.0 Amps 0.0 Amps
6:26 AM 1.7 Amps 8.4 Amps
7:40 AM 5.2 Amps 12.1 Amps
8:53 AM 8.9 Amps 13.7 Amps
10:07AM 11.9 Amps 14.6 Amps
11:21AM 13.9 Amps 15.0 Amps
12:35PM 14.6 Amps 15.1 Amps
1:48 PM 13.9 Amps 15.0 Amps
3:02 PM 11.9 Amps 14.6 Amps
4:16 PM 8.9 Amps 13.7 Amps
5:30 PM 5.2 Amps 12.1 Amps
6:43 PM 1.7 Amps 8.4 Amps
7:57 PM 0.0 Amps 0.0 Amps
It has a good comparison between the MPPT charge Controller and the simpler PWM controller (like the C30 from Xantrex). For the dual Kyocera example you would get 16.5% more power with an MPPT controller. The MPPT controller has some drawbacks though. It is expensive, it can generate RF interference because the DC-DC conversion process operates at high frequency, and some of them have minimum input power requirements like the bzProducts model that require 100 watts. Note also that the mppt controller improvement is inversely proportional to the battery charging voltage. It really shines when the batteries are nearly depleted but the improvement is not so dramatic when charging a battery that may only be 25% down.
I have verified this simulation with hundreds of measurements on our boat s/v Star over our two year voyage along the East coast of the U.S. and down to the Bahamas.