Found the customer service to be very good. I had some hiccups, that's for sure. They struggled with a few things during my routine oil change however, they were in constant communication and willing to resolve the issues. Took a bit longer than I expected and I won't be back just due to cost. It's definitely more expensive than my normal spot, and actually more expensive than my dealership. But if I was in a pinch, yes I would return.
Of course they are going to upsell you. Just be educated and be prepared. They may even have a coupon or two laying around they will give you.