The T-Roc is marginally wider, with a slightly bigger boot. Both feature plenty of head room and seats that go back far enough to accommodate all but the longest of legs.
In the rear, a Used T-Roc provides a bit more head room, however there is very little in it, and we would recommend visiting in person to test drive them both for size and personal preference.
The T-Roc does also feature a slightly bigger boot (about 8 liters bigger) and is wider, so the T-Roc is ever so slightly bigger.