Stylecaster says they are. I'm just not certain what types of vest are fashionable now.
I've always loved them. I have one I loved to death taken from a 1940's vintage mans tuxedo. It was a silk faille in front, low curved lapel and I replaced the carved black mother of pearl studs with some I found in an antique shop. The new ones were sterling silver mechanism on back and post, with the front being a 14K gold cup with a natural pearl mounted on it. Gorgeous and expensive for "buttons". I still have the vest and would like to do a knock off.