Vaseline is messy as hell. As a joke I call it the Devil's Goo. You are much better off using something as simple as possible, and I highly recommend you buy a bottle of generic baby oil. You can get one for probably $2-3 at most stores. I've never tried any specialty lubricants because they're usually too expensive, and you do NOT want to use moisturizer as it can irritate your skin and it's messy as well. I've also tried olive oil, which worked pretty decently, but it's a pain to clean up, smells bad, and can be semi irritating. Also as a side note, back when I did shower PE I'd stop the water to do jelqing and stretched while the water is on.
Hope this helped. Good luck finding a good lube bro!
-Dance