QUICK UPDATE: Sunforce is selling obsolete Sharp 12% efficient panels no longer in production at 123W/panel, 2 panels to a kit with a junky inverter and charge controller.. See my review at
Sunforce 39126 246-Watt High-Efficiency Polycrystalline Solar Power Kit but choose cautiosly as that product is from 2008 and is now obsolete which makes expansion of your system difficult due to the efficiency change.
---back to the review as it stood originally---
In evaluating solar panels (and systems of many panels) the typical pricepoint is $5.10/watt in high volume production. If you are finding better pricing than that something is wrong.
An example may be inefficient panels that use larger panels, causing massive panel size such that it is 4-8 times larger than this panel with the same output.
Other inefficiencies to watch out for are caused by voltages that are not useful. You could, for example, have a panel that output 500V at 1/10 A for 50W sold for $250 - looks good financially but very few charge controllers go much over 250 volts (and many dont make 250 volts - some are 12 or 48 volt systems). So that panel is not much use
This panel is in the sweet spot - enough power to be useful (80W/3 is a simple approximation for what useful power you can get with a battery all day long - about 25W or so given inefficiences. So theoretically it could support a 25W load 24x7 with an 8 hour day of sun.
The last inefficiencies to watch out for are panels that need heavy sun before they produce any output. Some panels produce usable (1-2 amps) output with just ambient scattered light such as a foggy day, while others give near zero output unless the sunlight strikes them head on. This panel design gives output whenever there is light, which is good. More light is always better, but it could be worse.
So to sum it up - there are no pitfalls here. It passes all the checks for pricing and performance. We load tested a string of 12 of these for a customer to profile their output to help decide if a rotator would help and it showed that very little gain would come from the expense of an automatic rotation system due to the panel's efficiency at many angles. With 12 panels we produced 1KW for 8 hours with taper up and down on both sides.
Best of all this can be used in series strings for grid tie systems or with battery maintainers