I acquired my PC-1403 as part of a general hankering for pocket computers that I owned when I was in high school. Back then I had two such machines that I remember clearly; a Sharp PC-1248 (similar in technology to this machine, but with a futuristic black rubber styling and a smaller LCD) and a comparatively high-end PC-2500 with integral graphical LCD and four-color plotter printer.
The PC-1403 straddles the boundary between a high-end programmable calculator and a fully-fledged computer. The main thing that separates it from contemporaneous 8-bit personal computers is obviously screen size. The BASIC dialect is fairly standard, but has some behavioral oddities related to the small screen; for example, it's not possible to have an INPUT statement with a prompt that's set at runtime; code like this:
10 PRINT "ENTER VALUE FOR POSITION ";P;:INPUT V
will fail with a syntax error at the semicolon after P. So it can be hard to write user-friendly programs on this beast. (The PC-1248's dialect, by the way, is much closer to standard). Apart from these issues, the BASIC seems to have the same general flavor as the Microsoft BASIC used by Radio Shack, et al; maybe it is in fact MS BASIC.
There exist a couple of emulators that claim to be able to emulate the PC-1403 but I have had operational problems with both of them. I'm still investigating this.