Solar Plants = any info/experience?

Back in 2010 I had solar panels installed and, until last year, they were brilliant. Investment cost recovered by year five so everything from there on was money in the bank - or so I thought.

Last August the inverter failed. Repairing it was more expensive than replacing it so I got a new one with a five year guarantee.

At a show recently we saw a stand for Solar Plants, nothing to do with plants but with a different type of inverter which takes each panel in parallel rather than in series. That claims to improve output by 15 - 17% and means that if one panel goes faulty, the others keep working, plus it has a 20 year guarantee. It all sounds good except it would take another five years to recover the outlay.

My gut feeling is that I'm better off staying as I am - especially as I only renewed the inverter last year (5 year guarantee but they have offered a "buy back" discount on it).

Thoughts?