For the sandwiches: Heat the olive oil in a large skillet over medium-high heat. Add bell peppers and saute 5 minutes, until tender. Remove half of the peppers from skillet and set aside.
Add onion and saute 3 minutes, until soft. Add sliced chicken and sausage and balsamic vinegar. Cook 2 minutes to heat through. Season, to taste, with salt and black pepper.
Using tongs, arrange mixture on rolls. Refrigerate remaining bell peppers for another recipe.
For the potato salad: To make the potato salad, place potatoes in a large saucepan and pour over enough water to cover. Set pan over high heat and bring to a boil. Boil 8 minutes, until fork tender. Drain and while still warm, transfer to a large bowl and add onions, cooked bacon, vinegar, and oil. Season, to taste, with salt and black pepper.