I've used Cryptomus for checkout. It was a terrible experience compared to other crypto payment processors like BTCPay. It has tons of trackers and fingerprinting and makes you wait for all the confirmations.
It's like custodial-to-custodial crypto is being normalized end-to-end, which is insane. At that point you have just reinvented the conventional banking system with extra steps.
but I think the advantage of cryptomus is that they have some sort of debit card or something that automaticially exchanges crypto->fiat whenever you make a purchase. Don't know because i'm not in europe.