I too have one of those that has not been turned on in quite a while. For RTTY the sound card implementations are a lot better, first because you can do better things with DSP, and second because the PK-232 uses a compromise 200 Hz shift for RTTY and AMTOR and Pactor whereas the standard shift for RTTY is 170 Hz.
But the PK-232 is a cheap way (cheap if you already have one) to operate AMTOR and PACTOR-I. I actually heard a station a few days ago using one of these modes, which was the first time in years I have heard any. He was transmitting in FEC mode, so I used a sound card program to talk to him, since sound card programs will transmit and receive in FEC mode. But I would have had to fire up the PK-232 to work him in linked mode. These days it seems the main use for Pactor is WinLink, and for that you need Pactor 2 and 3, which requires the expensive SCS box. Some of the recent sound card modes like Olivia are pretty amazing in how well they work without resorting to ARQ.