My business switched to AppStar after an unpleasant experience with another merchant service company. Our old processor raised our rates every six months with no notice until I was paying close to 10 times the national average for merchant fees.
I contacted AppStar and was promised a very low rate with very minimal additional fees.
That was five years ago. My rate is still lower than anyone else has been able to offer, and the customer service team jumped through hoops to find the right system to work with my business.
When I have called for information, or to update my account, the process has been both convenient and secure. I am very pleased with their services and can recommend them with no reservations.