I like how easy it was for us as developers, we just needed some time with our customer support team in order understand what they need from their platform so i can develop something customized accordingly! They're very nice people too :) We have used them since last year now but there are not really any problems yet except maybe when you get new features added by Google which sometimes makes you feel left behind (but still good!).
There's nothing specifically bad about this product or service at least if your looking for one then try out other products first before going forward only because of price tag/cost etc., otherwise no problem here ;).