So this is interesting topic that I have had a chance to experiment with all the players here in the states (google wallet, softpay(isis), and apple pay)
1. Google wallet is powered by a virtual debit mastercard and have only had success with using it walgreens and mcdonalds. You can add any card as a funding source though.
2.Softpay has alot of branded terminals and is supported in the US by T-mobile, Verizon, & ATT and works at all NFC terminals. Softpay for some reason blocks "debit mastercards" and accepts all other cards even credit mastercards. So its pretty suspicious of softpay. In my opinion i think they are blocking them to stop people using google wallet and go over to softpay.
3. Apple pay uses a type of secure token system but you have to have the banks approval so i dont think there is the same in between with a virtual mastercard that is owned by google to pay for things. I have been able to use apple pay at all NFC terminals even ones branded as softpay.
So after going through all 3 of these services apple pay is the most user friendly and secure plus the added bonus of the touch id for verification. Once all banks get on board everyone will start using it. They have done a good job at making it a universal form of payment compared to the failed attempt on by google.
I have to give it up to apple on this one for fixing a slow emerging and broken market.