Hi Davy,
New LG leds available on Ebay for 10p or less, so now don't bother with old strips as old Leds look a bit crumbly from use.
Most inverters are aware of a single duff Led and cut after a flash, or don't even try fire up.
Agree Leds in Series/Parallel would be more sensible, but think of the amps, thick cables and all those Schottky diode failures - Mind you, Schottky's are real earners on Vestels - Chris.