You basically want an oracle. That's fine, but none of what you just described requires a push model - you have a specific query, "best keyboard for me", so what you want is a service where you can go and explicitly ask that question, and get an accurate answer.

OTOH if an ad popped up and said "here's the best keyboard for you" - or even "here's the top 3 choices for you" - would you seriously trust that?