Buy another 100W light or upgrade to a 350 or 400 LED?

Currently growing with a 100Watt Spider farmer LED. But thinking of adding another light in there, another 100W making it 200W in total, thinking it would be beneficial because I can raise each light according to the growth of that particular plant (Growing 2 x White Widow Autos) but I am also thinking of using the 100W for seedlings/veg and just going all out and buying a 300/400 watt LED.

Current setup: Spider Farmer 60x60x120 tent with 100w SF1000

What would people's opinion be? 2 x 100W or go for the bigger light?

TIA!

I'd recommend getting a bigger light, but make sure it's a high quality unit.