He's overpriced in both cases (Slots and GNW Treasure) even though he now has BT. He's priced as if the meta were still what it was 2 years ago. His BT are good but nowhere near as good as say, Sage Kabuto's, and nowhere near as game breaking as SOSP's, two ninjas who are both available to f2p if they are willing to save coupons. And arguably they are cheaper than Founder Madara, for more real value. IMO there's no good reason to paywall/gatekeep him so hard.