I have a 80cm x 80 cm tent (31inc x 31inc), which the manufacturer of the light recommends. My problem is that i never saw a diary with this lights and i don't have the knowledge to compare them with all the vipar spectras, mars hydros,...etc
I use Vipar Spectra myself ( because im broke!) But i love the CoB set ups! When i upgrade, i know there will be CoB lights in the set-up!! Think its a great light for the size tent you have!!
This light is 120W, it's ok in veg but rather more for a 60x60cm in flower... If there's nothing in the manual about distance, just look at similar range other lights (Mars Hydro TS1000, Spider Farmer SF1000...).
For led's you want about 30-35 true watts/sqft, so a 200w led would be perfect.
I use the maxsisun mf2000 in a 2x2 tent, and I max it out at 50%, 60% started to burn my leafs.