I prefer using real plates and flatware, because they're more sturdy, and I would have no problem borrowing more if I needed more; when my brother and his then-girlfriend had Thanksgiving at their place several years ago, I packed up a tote of dishes, flatware, serving dishes and utensils, and tablecloths, and took them along, because I had them and they didn't

But at someone else's house, I wouldn't worry about it.
I have a set of 12 Christmas dishes I've used at Thanksgiving before (they're glass with a Christmas tree molded into them, so you can't really tell they're not "Thanksgiving" dishes) and I don't mind mixing those with my everyday dishes so I'll have enough. But I've never had more than 14 for dinner at my house.
I also have a set of 12 small glass buffet dishes I use for cocktail parties (I got them at a Goodwill store for $1 apiece) and a couple dozen mismatched wine glasses I got at a thrift store for about 50 cents each.