2 cents to consider:
- DCB metal has higher daily and monthly cap on accelerated RPs.
- DCB metal gives 10K points on 4L spend in a quarter , whereas DCB plastic gives two 500Rs voucher for a spend of 80K every month. So if you hit 80K every month, you will get 12000 Rs worth vouchers (BMS, OLA, Tata Cliq, Cultfit), which I think is easier to achieve than spending 4L every quarter for metal.