Drive Amsterdam to Antwerp, or will train hold 29in luggage overhead?

If you're concerned with your luggage being stolen it would be much more cost effective to purchase a lock like this than renting a car. There are multiple direct trains from Schipol to Antwerp, this will be the cheapest, fastest, and most comfortable way to travel between the two places. For schedules, fares, and tickets head over to this site: http://www.nshispeed.nl/en

Stephen, I wouldn't bother renting a car simply to transport your luggage. People in Europe regularly travel by train with a variety of luggage sizes, and problems are minimal. If the rail car isn't packed full, you should be able to keep your bags beside your seat. Even if you have to place it on the luggage rack, choose your seating so that you can watch it. Happy travels!

If you take the Thalys train from Schipol (currently, this is the only fast rail connection between Belgium and the Netherlands), I wouldn't worry much at all about bag theft. These are premium trains that make few stops. Consider the economics for a potential thief. The trains don't stop often enough to make "black riding" (ie, riding without a ticket) feasible, so the would-be thief would need to buy a ticket. The absolute cheapest fairs would need to be purchased well in advanced, and even these would cost at least €30 or so. Now, at a minimum, the thief needs to steal a bag that contains merchandise of at least €30 street value (not store purchase value- ie, your clothes and used digital camera are almost worthless for street resale). So unless this person is just a kleptomaniac, there's little financial gain to just grabbing random pieces of Luggage on a high-speed train. What I would not do, however, is drive from Amsterdam to Antwerp, one of the busiest and most congested road corridors in Europe, immediately after flying across the Atlantic. Driving under the influence of jet lag is about as safe as driving under the influence of alcohol.

Also, renting a car in one country and returning in another results in hefty drop off fees.

If this is one 29 in. bag for the two of you, have you thought of using two 22" bags? If you are moving around a lot, that's a bulky size. If you are going to one place and staying, you could get away with this.

It's not just your BIG bag that you should be concerned about loosing. My husband had his little bag stolen from the rack above the seat at the Antwerp train station. It was the train to Brugge and I think the theft occured before the train left the station.