commission in both of Orbit and 9wickets is 3% on winnings , which is lower than the standard betfair but as I understood from support commissions don't get lower lower even if you wager hundred of thousands with them unlike betfair where high rollers get discounts
I didn't get what you mean about premium charge , can you explain it ?
3% is not too bad given what you are getting (i.e. access to Betfair markets with BTC and no KYC).
Premium Charge is an *extra* fee that Betfair charge long-term winners. They introduced it years ago, this is from their website:
https://en-betfair.custhelp.com/app/answers/detail/a_id/6156/~/premium-charge---what-is-it%3F-will-i-need-to-pay-it%3FBasically, it was introduced to take a bigger chunk of the profits their professional users were making. And because of their market position it is something a lot of very unhappy Betfair pros have had to put up with. A source of continued irritation to most.