Well, let's start. I had 2GB or memory on my computer and needed to upgrade it for a school project. I chose this because of reviews and price. I ordered it on a Saturday. Monday evening, about 7-8 I got an email saying it had been dispatched, and it arrived before I woke up in the morning! (7:20) I was shocked about how quick it was delivered.
Anyway, performance wise, it has created difference. Having Ubuntu, I don't seem to lag that much anyway, but where it does get slow, it doesn't anymore. I can shut it down in 10 seconds, I was amazed. So I would recommend the product to people, as it is a good improvement, worth the money.