Dave, here in the "Old Dart" (wtf?), I have a 4kWpk system. We are further from the equator that you are, so longer summer days mean I am able to beat your figures for 2 (maybe 3) months of the year, in high summer. But you've got me beat, the rest! Check out how much your solar power waxes and waynes through the seasons, and compare it to mine (PVoutput user Wilkins_watts). Very low power in the short, cold winter days!
Like you, I went for a premium system of Sanyo/Panasoinc panels and SMA TL4000 inverter. It just all works. The system has been in 3 1/2 years. I paid TOP DOLLAR (about USD $16000 equivalent - ouch, yes), as did many other "early adopters." Yes we, too, saw something of a GOLD RUSH, until the government turned down the Feed In Tariff scheme, somewhat. Still, my system will also pay for itself in around 6 years, then I can sit back and enjoy the overly generous gov't susbsidy, which continues for a further 18 years after break even WOOOOOO-HOOOOO.
Most Brits move house, on average every seven years. There are just over 500,000 solar PV systems in the UK. When doing the payback calcs, a major and hard-to-quantify factor in all calculations is "how does the housing market value a solar installation?" The jury is still out on that one in the UK, but I think attitudes are changing, as people slowly "get it".
There is another side benefit, of course, in that it makes you THINK about every kWhr! "The cheapest KWhr is the one you never burned."