Well, I have a Nexus 7. I like it mostly.. There are only TWO things I don't like about it.. 1) No back camera, only one on the front. 2) Very flimsy charger. When taking the charger out, it feels like it's going to break. Other than that, I like it. :)
You definitely purchases a very nice device. It's up to you whether you like it. I wouldn't say it was a mistake but you should always do research on a product before buying. Fortunately the salesman recommended you an amazing product.