Awhile back, I bought Urban Decay's Eyeshadow Primer Potion because of many great reviews and yes, it is a great product!
THEN I started reading the reviews about the packaging. Basically the packaging is terrible because when you think you're out of product, there is still a ton of goop at the bottom and for $17 I want ALL my goop! Around the same time that I bought this, I had a free sample of Two Faced Shadow Insurance in a very small tube. This product is great, has better packaging and is the same price as the Urban Decay Potion.
I had the small tube for quite awhile and completely avoided the Urban Decay Potion as I desperately looked for my receipt for a long time. More recently, I was shopping in Sephora and I overheard a manager telling a customer:
"Oh just bring it in without a receipt and we'll swap it out for the other one."
I quickly walked up to him and told him about the Urban Decay dilemma and he said I could just bring it in to swap it out! SWEET! I finally got around to doing this at the conference in Boston (remember I told you about all the stores?) and it was so easy! No questions asked and I got my Two Faced Shadow Insurance.
Also, right now at Sephora you get 5 free samples with every order online! It's usually 3 so take advantage of this offer if you can! It's also important to become a Beauty Insider because the more points you accumulate the better your samples are.
**UPDATE: Sassy Little Ginger commented and said if you use the promo code FRESH, you get a free sample from the Fresh brand as well. 6 samples! Thanks Sassy ;-)