So I got into a debate with a friend about getting a vamp scepter. He never buys it cause he claims that he never needs it. I believe that it's very useful to sustain in lane with but he won't listen to any of my suggestions. My question to you forum is when should you get a vamp scepter?

I usually get one on the first trip back, if I can afford it.

I tend to buy it pretty early on, especially if I'm being harassed early game in the lane. However, if I don't make enough money to buy a good enough item when I go back, I'll buy a vamp scepter

vamp scepter is incredibly important. the constant nerfs bloodthirster is getting should tell you how strong of an item it is already. i usually buy it after my two dorans. if im on my first back with 1650 gold. i would not buy the BF Sword. I would finish off my boots and 2 dorans, if i have more money - ill get that vamp scepter and pots.

If you need the health, get a dorans over vamp sceptre. But if you don't, vamp is good to get

If I play ADC I like to go boots potsx3 to start then go back and if im doing well two dorans and vamp then either IE or BT depending on what ADC you play. But it does make a noticeable difference in lane, so much sustain from vamp and dorans early to mid game

if you have a healing support you can skip it for awhile, I like to go either boots 2 double doran, or if i can delay my first b long enough ill get pickaxe and a vamp scepter

I play ADC a lot, and NEVER get a vamp scepter as one of my first items. I generally get Doran's, Boots, then just save up for my BF sword, and THEN get my scepter. I'd rather be a little more defensive until I can build up that damage needed to completely shut them down rather than both ADC's having a scepter just barely managing to sustain themselves in lane.