-Adding an extra component into a spinning portion of you vehicle, meaning one more thing that could fail and potentially kill you.
-Tires will spray rocks/mud/debris more up the side of your car on the paint.
I don't know anything about that brand, so I can't offer advice there. I would just say to not go with the absolute cheapest ones you can find. Find a company with a good track record even if they're $50 more or whatever and you should be fine.
I plan on just getting aftermarket rims that are 1" wider and will stick out 1" further. I saw a post (not sure if on here, or a facebook group) where the guy had 1" spacers. It looked good and didn't push the tires out past the fenders much at all.