What is the general consensus?

You will still be on major arteries, so what is the difference? The only time I would deviate from the "straight line" path would be if it was advantageous to do so because of traffic, however all too often, the beltways around the city are also congested.

I usually take the loop

However, you may want to drive through to get some experience under your belt. Practice makes perfect and you never know when you may have to drive through downtown.

Here in Southern California we are often in bumper to bumper, stop and go traffic, it's nice to know how the RV and I handle the traffic. It's also a good way to determine if your cooling system is operating properly.

If you can do it during a time of day when traffic is at a minimum go for it.

I pretty much can't get off Long Island without going some part of through NYC. I plan my departure time so I'll miss the major traffic during the morning rush hour.

Why drive thru downtown if you don't need to, I tale the beltways with my car!