i work for a PV company as a salesman/surveyor (an honest one)((yes they do exist))
i have recently been visiting customers that we installed PV for a year or so ago and they are ALL getting more money from the feed in tariff than we predicted, we are however based in Cornwall.. so get a fair bit more sunlight than Sheffield (which is where the SAPS calculation is based from)
panels have recently gone up due to i new chinese export tax, but we can still get ours day to a 6 year payback time (which in reality will be lower) they are still fair cheaper than they were a year ago but the tariff is lower!
Still worth the money in my opinion, much better than having 7-9k sat in the bank in my opinion! after you’ve paid the system off, the calculations show that you will make between £20-26k from the FIT!