Which method would be most reliable and suitable?

I was thinking of starting a Questing Service but somethings stops me from doing that. There is ONLY 2 methods that I can receive payments from, PayPal and RSGP. I heard with PayPal that people can chargeback whether it's sent as gift or not but at the same time, when RSGP is used as payment, not everyone values RSGP at the same rate which will result in big price gaps between two Questers. Another problem is that Questers always cut you when RSGP is used, as 1.5M to some Questers is a lot of GP.

My question is, which method should I use that will be most reliable to me?

 

I'd say do both, people won't chargeback a small amount, as the price of quests are.
If they want to use RS Gold let them, just charge them a price that you think is fair, perhaps .75/M