Lodash, hands down. No project operates without dependency and I'm going to say that Lodash is a necessary dependency. I come from a heavy underscore.js background. So, I obviously love Lodash.
For starters, the readability of Lodash is beautiful compared to JavaScript's Array reduce.
The problem with native JavaScript is that, you have to write your own functions on the fly and different engineers in your team are going to do it in different ways. Not to mention, if you're writing your own functions, there's a possibility of it being error prone.
This library is developed by people, whose job is to make sure the functions they offer operate at a very optimal level. I would strongly recommend to go the lodash way rather than the native way, but hey, that's just me. I am guessing Sai Kishore Komanduri will have some views that are rather different from mine on this.