I stopped eating white potatoes for a couple of months, then had some mash potatoes a few nights ago and found I couldn't stomach them. They were prepared from the same recipe I used for years, but they tasted horrible to me.
I'd like to offer a hearty "both," even though I voted for "regular" potatoes. There are WAY too many varieties of "regular" potatoes to ever compare them as a group to sweet potatoes.
I challenge all of you who pick "regular" potatoes, next time you make a batch of mash, try adding one large sweet potato for every four potatoes. EVEN if you think you hate sweet potatoes! You'll never go back.