I have just installed a 5KW solar system on a double story tiled roof. The roof space I had meant that the panels needed to be installed in a NE direction, and I needed to split the panels, 12 on the top story and 8 on the lower story garage roof. I did a fair bit of research before going solar, in particular reviews on panels and inverters. I decided in the end to go with Renesola panels (20) and a Growatt 5KW Inverter which has Dual MPPT. This is important, as I learnt with string inverter systems, the system is only as powerful as the weakest link. One of the panels on the lower story would be shaded until around 11.00am, so output from that section of roof would be lower until it was all in full sun. By having the Dual MPPT on the inverter, the top story panels are in full sun and generating full power from early morning (3KW), then once the sun hits 11.00am, the second section is in full power (2KW). So all up the system is showing about 4800W power generation when at peak and have been able to generate 25KW of power each day. I would recommend that anyone looking into Solar first shops around, you will likely be offered the cheapest panels and inverters, do some homework, I probably spent $1000 extra in choosing better quality Renesola panels but think it is worth it, the whole system set me back around $5700. I chose Evergreen Solar as they seemed to have the best pricing for the system I wanted. They were professional, they came out to my house to do a pre sale inspection and I got a written quote afterwards to make sure there were no installation surprises (such as meter box upgrades etc). The installation guys were very good and knowledgeable, it was a shame that they started work on a Monday, but due to poor weather only made it half way through, surprisingly they came back the following Sunday to finish it off! So at this stage I am very happy with the choice of going with Evergreen and the system selected. The only very minor gripe I had, now that I have the system I wanted to setup monitoring for it, Growatt have a WiFi adaptor that you can connect to the Inverter and connect it to your home ADSL WiFi router, Growatt have a web site that you can then log onto to view the power generated out of the system…Evergreen don’t sell this and I had to get it from another supplier ($130)….there is a bluetooth wireless monitor they do sell, but from my perspective I want to see daily and monthly generation trends…so something I would recommend Evergreen look to supply as well in the future. Otherwise they did a great job.