Luggage on the 17?

I am planning to take the 17 from san jose to get to ucsc, I was looking on the website and it says that metro is "enforcing and limiting carry-on items by asking customers to only bring one carry-on item that can fit on one's lap"

I'd be bringing a typical large rolling suitcase and a small duffel bag, would this be okay/does anyone have experience taking a suitcase on? or would I need to find other accommodations?