Idk what fjack is... But yeah, I'm not affiliated with premium ads if that's what you mean. they are just truly the most stable accts I've ever used in my life, aside from my own relatives. So when ppl ask or seem like they need accts, I tell them what has worked for me. Mainly because that's the only seller I've come across selling accts with real daily activity from the actual user.
You want me to say something negative about the accts from Prem ads? OK.. They are expensive, sometimes dude is slow to deliver (I waited 3 weeks once after spending $2500 for a group of accts), adding credit cards can be tricky and I refuse to pay 10% or 20% for a VCC, their older accts didn't have 2fa and coordinating with the acct owners (the actual people who the acct belongs to) is like pulling teeth. I literally have one of their accts sitting disabled right now because of 2fa. Ads are running, but I can't do anything bc they have to get with the acct owner which can take time and sucks. These are all negatives that are annoying.
So just being honest, it's not all sunshine and roses, but end of the day idgaf when I can spend multiple six figures in the accts and they rarely get restricted. I've bought accounts from many vendors. They all say they have the best accts that are super solid, but almost all of them are trash. I think the future is procuring real profiles either through your own methods or via a vendor. Farmed accts or accts that don't emulate real user activity are going to become completely unusable, in my own personal opinion (YMMV of course).