But would it be safe for a payment processor to rely on SPV?
For example. Bitcoin.com wallet does strange things: low fee tx appear and disappear suddenly in the balance screen. You have to be sure that your POS detects low fee txs and warns you
I am considering using bcash made by Purse.io, since it can run in SPV mode. I will check if I can query the tx fee in this mode. If the fee is below 1 sat/b ....