Panels with glass sandwich and aluminum frames weigh about 20 lbs per 100 watts. There is probably substantial weight added by the mounting scheme.
If you look at the cost of good panels, which is about $1/watt, it is in general better to add 20% more panels to a permanently flat system than it is to build a tilt mechanism. A 20% larger flat system would produce the same power for most of the day at continental U.S. latitudes compared to a system with one tilt angle set for the entire day. If you track the sun, you can beat the flat system close to sunrise and sunset, but at the cost of having the array raised to 90% at which time its wind load would be problematical.
The biggest problem is that panels handle shade poorly. Mine have three diode strings per panel, and if you happen to obscure a cell in all three strings, the panel stops conducting. I would like to have panels with a diode per cell rather than a string of cells per diode, that would probably work better.
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