There is a limit of $1000 per book per year now.
Ive only done 5D and Pinny cash... oh and I used to take bookmaker cash too. Think there is 1 or 2 others we can use. SAI I think is one. Check the SB cash page.
if you can join Pinny as an SBR referral you'd be crazy not to. 1500 points = $100 with 1x rollover at Pinny and 3x roll at 5D