So is there actually any difference if I buy an OTC benzoyl peroxide as supposed to the one in the regimen? I mean, at the end of the day, they're still both BP's right? Lets say an OTC BP with a concentration of 2.5% or 5% compared to the Regimen's BP.

I feel like I can answer this now since I have tried both.

The main difference is price. You have a ton buying Dan's big container and it lasts you a long long time.

Aside from that, Dan's gel BP doesn't leave white streaks. There are creams out there, but gel based is invisible so it is much better.

Also, Dan's BP is really smooth and it glides on your face so much easier than others.

When I started the regimen I used Benzac and it got me clear, but now I love how Dan's BP is even more refined than the Benzac. Not in the least bit grainy. You skin will still feel like skin when your skin gets used to the BP and if you moisturize correctly.