Little update, woke up this am & one of my 1000watt ballasts had died, so had to go 20 odd miles to replace the bastard under warranty again, but 5 year warrantee least they uphold it no question, I dont even got a receipt. Adjustawatt shite. They changed em now & added a fuse so maybe sorted whatever was the fuck up.
Moral of story, dont be a tight arse & travel half way across the country to get a good deal on some grow lights.
I doubt they have changed anything other than the position of the fuse to the outer panel (if that's the case). I very much doubt they are power factor corrected so when the thing is powered up there will be a significant inrush current as the storage capacitors are charged up. They'd normally use a device to limit this but it can still be significant (50Amps isn't out of the question).
At a guess I'd say they were sick of taking them to bits to change the fuse
If it ever blows make sure you replace it with precisely the same type, I'm not just talking current rating either. There are three basic types, anti-surge, slow blow & standard & I'm guess the one used will be in a ceramic case to avoid it rupturing.
You'd need to go to an electrical factor to make sure you get precisely the same type as they'll be able to identify it from any markings
Good luck with the skyscraper, think Empire State Building & a rather large gorilla