Yes, definitely let @dbrn32 fix ya up. He helps tremendously! I should’ve consulted the forum before buying my light. TBH any of those lights on amazon are crap, they don’t actually pull “1500w”, more like 200. It’s all a marketing ploy, I fell for it too. I believe in a 4x2 you need about 400.
You have narrowed down to those two? Both are a little small to do 2x4 by themselves. I would consider maybe going with a better light, or going to slightly smaller fixture and getting two of them.
The main differences in those two fixtures is the type of light that will be emitted. One will appear purplish and the other white/yellow. In terms of quality, the vipar is probably built a little better.
If you want to look at a very good fixture for the space, check out qb 260 xl kit from horticulture lighting group. They’re available assembled from growerslights.