$700 for 160 watts of solar INSTALLED is a little steep; but not near as bad as some that have been posted here. The equipment appears to be of decent quality, and the design seems solid; if this were a MPPT controller instead of PWM, would be good.
Its not a trivial job, but if you feel very confident of your DIY skills you could do the same for less than half the cost.
As ktmrfs pointed out, fixed mount panels have drawbacks. I have 120 watts fixed and a 100 watt portable panel. Without the portable, I would probably have to run the gen now and then. As is, I only had to use the gen a once this year.
Regards,
Doug