As with every other pp - absolutely not!
If he had your best interests at heart, rather than his own immediate gratification, he wouldn't want him for you either.
That kind of age gap at your age is either a hell of a mid life crisis or possibly an attempt to get an inexperienced girl he can control. You may be very mature for your age, but the power dynamic is still huge and unbalanced, and not at all to your benefit. Ditto money, life experience, energy levels, everything.
You said you're 6 yrs older than his oldest - TBH, he should mentally be thinking of you almost in the same bracket as his kid, and the fact that he's not, and is flirting with you etc makes it massively more creepy than the "standard" level of creep of a middle aged man wanting a barely-adult teen.
When you're 40 & still in prime of life, he'd be 60. He's already got kids, so you'd be tied to his schedule and all of that, and he's unlikely to want more with you if that's something you'd want in the future. Plus even if he did, he'd be exhausted by then and unlikely to be the father you'd want for them.
He might not now, but many men start having ED problems in their 40s as well...
Go enjoy your teens and 20s with guys around your own age, who you'll have a viable future with.