Ditto. Any internist who is interested in ordering a Tromner hammer is way ahead of the game in my book. Honestly, if you aren't planning on carrying it around with you, the Queen's Square is my favorite. You can also get the pedi version if you want it to be more portable; it works almost as well.
The Babinski hammer is very similar to the Queen's Square, but the handle is non-flexible. A telescoping Babinski can be useful and portable, although I hate the joint at the head.