I don't know of a dual use product but couldn't you use a Belgian waffle maker to make regular waffles. The batters are different. Is it an issue that the regular waffles would be thick like the Belgians?
"If you want to make an apple pie from scratch, you must first create the universe." -Carl Sagan
I like regular waffles and belgian waffles. I like that regular waffles are crisper, thinner, and have smaller areas for syrup, butter, or sometimes even peanut butter. I like belgian waffles because they are fluffy, less crisp, and have deep areas to hold whipcream and fruit.
Neither grid pattern can make both.
I would really like a waffle iron that has removable/swapable plates for each grid pattern.