Solo use
For one person, a lid that serves as a cup can simplify the packing list. Check the cup's capacity and whether the vessel can be cleaned on your trip. Compare the total packed weight with a bottle you already own plus a lightweight cup.
Shared use
If more than one person drinks at the same time, a separate cup may still be necessary. The integrated cup may become a backup rather than a replacement. Do the count before paying for a feature that will not reduce your kit.
Avoid the photo test
A polished campsite image cannot tell you whether the cap is comfortable to hold, whether it fits your routine, or whether the size suits your bag. Read the manufacturer's product dimensions and care instructions. The Stanley 1 QT bottle is one option with an insulated lid described as a cup.