I Am using this Site or App from past 3 years and until now I have not came across any kind of issues. even though there are few issues like payment will be processed but no recharge are addressed very well in my experience.
I do lot of recharges either it be mobile operator or data recharge or DTH payments everything got successful and you will get limited period coupons on recharge as well but I have not used them till now cause I dont prefer to the brands on which they provide offer. Final verdict very gud site:)