Dips racks are dip racks in my opinion.

The only difference is really how sturdy they, especially when it comes to the home versions that aren't bolted down. If your a bigger guy I would try it out in store to make sure its not going to move around on you.

They also come in straight and angled bar versions, so you may want to try out both to see which you prefer. I personally like the angled bars.

When I was into home gyms I got most of my stuff at New York Barbell. They have a nice selection of chinning and dipping stations that you may want to check out.