Are Corporate Fixed Deposits Safe?

Please tell me is it safe to invest in corporate fixed deposits?

Compared with your usual bank fixed deposits, corporate fixed deposits are a bit risky. Since corporate fixed deposits are issued by Housing Finance Companies, Non Banking Financial Companies, they are not as well regulated by RBI. Moreover, corporate FDs are not covered by DICGC insurance further making them a risky investment than bank FDs.
I would say that if you are considering investing in a corporate fixed deposit, you should definitely check out the issuers credit ratings, ICRA and CRISIL ratings and the financial reputation that they carry in the market.
I would like to hear your thoughts too on this.