If there is a proper silicone seal between the drainboard and the sink the reveal, flush, positive, or negative, should make no difference. The sink extension from the cabinet is personal preference, but 1-2" is usual.

Do you mean a drip edge under the sink that is made of countertop material or do you mean a drainboard with channels cut into the counter?

I don't have a drip edge but my farm sink protrudes as much as my full overlay cabinet doors. I didn't know about drip edges before but I would have it extend a little further than the doors to catch the drips. I really wish I had done one because my painted doors under my farm sink are peeling a little from my messy dishwashing.

It is,a board that sits under the sink and protrudes further out than the sink. My cabinets are white, but the drip board is walnut to match my baking counter.

This is what you're talking about?

Kitchen, Stockton, NJ · More Info

Ultimate Farmhouse Kitchen · More Info

Actually, couldn't the water get caught under the sink?

I had no problems in my last kitchen with my farmhouse sink and water dripping.