I am relatively new in flashlight. I am curious Fenix is better ?Or Nitecore is better? Cuz last week I went to flashlight stores, some of the sales told me that Fenix has a better temperature control system; Nitecore copies Fenix design; Nitecore makes better light bulb, etc. Their comments are quite contradict. Not sure were they trying to hard-sell me. Can someone tell me ? Thanks!!!
Your question is very simple…however, you posted it in the wrong forum…you will get so many contrasting replies (and surely will not be limited between Nitecore and Fenix) that I will bet you 2 to 1 you will end up more confused than before… 
If you’re talking to sales people in a retail outlet, you’re beat before you start. Tell us what your needs are….what you want.. You’ll learn a lot hanging around here. You’ll end up broke, but you’ll have some nice flashlights at prices you won’t be able to resist! 
Oh, and be prepared for ten opinions to every question. Ask “What’s the best” and you’ll drown in opinions! 
I think I prefer Fenix over Nitecore by looking at having just one Nitecore light EA4 among many Fenix lights I have. This EA4 has high parasitic drain on batteries, make it a useless light.
Fenix is better in terms of design but it’s just my personal perception of these two brands. Nitecore build quality is good too though, just that design wise not as good or as stable as Fenix.
Thrunite
I used to really like the fenix flashlights like TK45 and TK41, but then they discontinued those and started making things like this:
lol
So now I like the nitecore looks a lot more.
I’ve found both my nitecore and fenix flashlights to have great build quality.
I never thought of it, but I guess my answer would have to be Fenix I have several of their lights. I don’t have a Nitecore yet though.
TK41 and TK45 are both NIMH battery powered. I only have Fenix TK70 NIMH powered. I am waiting for neodymium magnets to put 26650 in it. All my Tenergy D cells get rusted.
I never stepped into a flashlight shop/ store after I discovered BLF lol
Just tell us what you’re looking to spent, size and expecting output (in lumen or cd), battery type, USB or no USB. I’m sure someone on here will have an answer or at least a good suggestion for you to pick from.
Wich models were you looking at in the store?
I wouldn’t say one brand is better than another on the whole, the design and ui option differences are what should draw you to them. Not all Fenix are built like tanks, as some are designed for professional use and some got home use and are marked as such.
Nitecore takes some cooler design chances over the years, and fill some size to output preferences better.
For the size, battery type and use of light your looking for, will change which ones better.
I would definitely pick FENIX. I only had One[1] Nitecore. An EA4 and I sold it about 3 years ago.The parasitic drain was definitely an issue.
I have 5 FENIX lights,they are all modded[like most of my lights]. They are reliable, built well, great output, heat is managed very well and CAPO likes them! 
After owning a few of both, I’d vote Fenix, even though not much of their product line excites me these days.
I would certainly agree with you on this.
They have not kept up w/ Acebeam,Thrunite and a few others in the long throw dept. and exciting lights in general.
Most that I have are older but goodie Fenix lights.
PD12vn,TK35vn,TK61vn V4,TK75vn QUAD SST40 SD[On the way] and PD35vn.
There are things I like about Fenix and things I like about Nitecore. I’ve never had any problems with either of them. Overall I think I prefer Nitecore over Fenix but that’s just my personal opinion, I have nothing solid against Fenix I just prefer the UI on the Nitcore (with the exception of the MT series, not to crazy about those) over the Fenix.
I think quality wise they’re on the same level. They both have their own unique lights, so it’s a matter of what kind of light and features you want.
Take the best of both, and buy Acebeam
nitecore EC4S with xhp 50 is one of the best lights imho
make sure to get a coupon code
nitecore EA45S is another must have XP-L Hi light. takes 4 AA batts
make sure to get a coupon code
i like fenix aaa lights also
I like them both but I own A LOT of Nitecore flashlights and only 1 Fenix, the UC40UE. The UC40UE was my first “good” rechargeable light that I bought. Previous to this, I had bought a Streamlight Scorpion then a Streamlight Pro Tac HL and I thought they were both great lights. Now I have a lot of different brands and many favorites for different needs and situations. I can justify them all lol
I have both brand popular flashlight. Those are Fenix pd35 and Nitecore p12. Although, I like fenix brand flashlight but If i compare between those two flashlights then Nitecore p12 will win. Features, beam distance, price everything will beat the pd35. So, the brand comparison is useless for me. If you compare model then it will give the more clear idea. I have added some difference Fenix vs Nitecore in this article for better understanding.