We tow a 4 door Jeep Wrangler - right around 5k pounds I believe. Before that was a 2 door Wrangler. I used a
Brake Buddy for both. IMO, you don't need one all the time, but when you DO need it, a guy is happy he has one :)
I think if I buy another braking system, I will go with the SMI Air Force One. It runs off the coach's air system. They aren't cheap, but super easy, and no bulky braking system to store/move/hook up.
However, been very happy with the Brake Buddy. Keep an eye on Ebay and Craigslist for used ones. They typically go for about $500 used.
As for front end protection, I have a big mud flap on the back of our coach, and don't use anything but that. But, again, I drive a Jeep, and it sits up higher than a normal car, and not as much to chip up on the front.
--kev