VetRex may be used internally by mixing one ounce to each gallon of drinking water, or externally by a few drops to affected area, for sore throats, sore toes, scaly shanks, eye worm, etc. 2 oz. Bottle
Pros - Helps sickly birds (somewhat), makes combs red and beautiful
Cons - Isn't really a treatment, dries out combs A LOT, oily
I've used VetRx for sick birds that I've had. I've given it to them in their water, orally, and in the nostrils. It does not appear to be a real treatment, in my experience. It might help alleviate some of the symptoms, but has never cured my birds. Still, I've heard that some people have had success with it.
As for a comb dressing at show, VetRx does make the comb and wattles shine. It is a little oily and hard to control sometimes, but makes them look pretty (just don't get it on the feathers or your clothes). However, within two days or so of the show, my bird's combs become extremely dry. I believe that the VetRx causes this, so keep that in mind while using it.
Cons - I don't think it's really a con, but since it's oil based, it can be messy.
A friend that raises and shows chickens brought me over a bottle of this stuff when I told her my old rooster has a rash that won't go away. We rubbed some on his rashy area, legs and his comb. He seemed to really like it. I also put a few drops in their water. I can't say it cured his rash as it's still here-but improving (and I'm using another product on the rash as well), but he just seems to be doing generally better. I had a lot of the product on my hands, so I wiped it on hen who had lost a ton of feathers (due to bugs I think). I just rubbed it on her back and sides. The NEXT DAY her feathers started growing back. It could be a coincidence....but I love this stuff!