When playing a wide stretch lick on the high e string, frets 2-5-7, i find it most comfortable using my index/ middle/ pinky fingers. Watching videos online quite a few use the ring finger instead of the middle.

Does it matter? is it worth trying to play the lick both ways?
It'd help if you'd show us one, or some of the videos you mention. Aside from that, a few interesting statistics and methods, make of them what you will.

I very rarely see people use their pinky-finger on their fretting hand, eventually they do it, but very often it gets a bit disregarded. This is the same for the strumming hand, if you are fingerpicking, though supposedly Heitor Villa-Lobos was an exception. That doesn't mean however that it's something detrimental to your playing, your playing being what you play, not copying someone else's material. There are a fair few gipsy guitarists that neglect their pinky finger most of the time, but show incredible virtuosity. Guthrie Govan doesn't use his that often either, from what I've seen, though I can't say I've studied them to the extent some may have.

One of my teachers at conservatory one told me that women tend to make the stretch between their ring finger and their pinky, whereas most men seem to stretch between their middle finger and pinky. This was not an opinion of hers, she simply noticed it over 50 years of teaching at convervatory, nor did she approve or disapprove of either method.

Anyway, I dislike stretching between my ring- and pinky finger. It is possible, but the way the tendons connect those two fingers I find it uncomfortable. I do however, in the case you describe, prefer to stretch my index finger away from the other two, rather than stretching the pinky away from the index finger. The index finger is very strong and accurate, the further you go away from the thumb and index, the worse those two factors get. Figuring this, I've learned stand on the outside of my fretting fingers, when playing. I'm afraid I can't provide pictures to show you, but if you'd wish to try how it feels, I suggest playing that line of yours backwards, placing all the fingers at the same time at first. I find it does give a more secure fretting hand, though it may require some getting used to.

Good luck
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