Hi @mudlu
I have heard good things about Positronics, so that covers the most important decision for buying solar:
Who Should I Buy Solar From?
Quality products, price is fine. I don’t have a strong opinion on whether you should get the higher wattage panels or not. However, if it’s not a financial stretch, the TwinPeak do seem enticing 
Would love to see a photo of the install once it’s up.
Cheers
Marty