Have both... had the trailer first and that's probably what I would advise. So what if it sits in the winter, it's still very versatile. In fact the dump trailer gets towed everyday by the dump truck (dump truck carries the tools, lol)! We would rather work out of the dump trailer for almost everything! Someone said they "sit too low" but that's the best thing about a dump trailer. Also good for ramping wheelbarrows into... we do that a lot. You can fit more in it. I see more and more guys this year with dump trailers.
BUT Be sure to have a truck that can handle the weight!!