The best thing I like about this service is that it's free for first 30 calls per month, so if you're just testing out the product then there isn't any risk involved in using their products. There are some minor bugs here and there but nothing major to write home about. I would say try them out before making your final decision! It was easy to use and set up compared to other solutions we were looking at. We needed an API solution that could be used by our mobile app which allowed us to verify numbers without having to rely solely on text messages or emails.