That poll is a little bit bias, because Plus has great features (I usually work around them, but wished more than once we had bought the Plus license!). But the question mention performance boost, which is the least reason I would consider the upgrade. Is NGNX your performance bottleneck? If so, either your service probably don't do much (no critic there, just to mention the processing of the services behind nginx is super low), or there's some misconfiguration - like costly regex - in your nginx setup, or some architectural problem. In short, Plus has some great feature, but if the reason to upgrade is to get a performance boost, I would step back and analyze my stack to understand where are the current performance costs.