Two snails? depends what kind. Some are asexual, some do need a partner... In a 10 gallon the pleco won't last. It's too small for him >< otherwise trust me I would have gotten a couple =D Plecos get bigger, and need a lot more space. The fish and the snails are just fine however. I don't remember plecos eating snail eggs... so no idea about that.
If you ever run into a snail infestation, use a leafy green vegetable and they'll go on it, which then they can be removed. I had a fake plant the snails loved o_O bad plant for bettas (rough) but never caused a problem with any of my bettas... And the snails were easily removed since they crowded on that plant lol.
Breed for the breed, not for the money; the words any REAL breeder would understand.
You must know nothing in order to know all, for all is nothing and nothing is for all.