ChipFlip
Budget power supplies are the one component where saving $15.50 can cost you the whole machine. The EVGA SuperNOVA 850 G+ sits at $65.00 used, the EVGA 650 N1 at $49.50. Same brand, opposite ends of the range.
The N1 is EVGA's entry tier and it shows
Non-modular, no 80 Plus Gold rating, and built to a price. It will run a modest system with a low-power GPU, and for an office machine or a light build that's a defensible purchase.
What it won't do is handle transient spikes from a modern mid-range or high-end card, and non-modular means every unused cable stays in the case.
The G+ is a different class of supply
Fully modular, 80 Plus Gold, and 850W of headroom. The G+ series has a solid reputation for regulation and quiet operation. For $15.50 more you get a supply that can run essentially any single-GPU build you'd assemble.
The efficiency difference also has a small ongoing cost attached. Gold versus an unrated unit means less waste heat and marginally lower power draw for the same work.
The failure-mode argument
A power supply that fails badly can take other components with it. That's the reason the usual advice is to buy quality here even when economising elsewhere. The N1 isn't dangerous, but it's the tier where corners get cut, and it's the tier with the least margin when something goes wrong.
The EVGA support caveat applies to both, since both are EVGA. Check age and ask about warranty status either way.
Bottom line
Spend the extra $15.50 on the G+. More headroom, fully modular, Gold rated, and it removes the power supply as a constraint on future upgrades. The N1 only makes sense for a genuinely low-power machine you have no plans to change.