I have used swiggy multiple times and I have not been disappointed. Although the delivery takes a bit of time, the service is great. Especially the customer service.
Ones I had ordered food from The Spot from kanjurmarg and when the food had arrived, the extra sauce which I had paid extra 30 Rs was not there. I immediately contacted the customer service and was asked if I wanted to wait for it to be delivered or to get the refund. I had asked for a refund and immediately the refund was processed back to my paytm account.
Another instance was when I had ordered food and the delivery guy asked me to cancel the order and reorder it as he wouldn't be able to deliver it. Since I had prepaid from paytm, the amount had been debited. So I contacted the customer service and on explaining the situation was informed that the amount will be refunded and was advised that if such a situation occured then I just need to contact the customer service and they'll handle the rest.
Although the delivery seems a bit off, the customer service has redeemed it and has made sure that they haven't lost a customer.