Roland recently reissued many of their classic synths including an updated 303. Now it’s called the TB-03 and it has a “friendly” step programming option in addition to the original crazy style:
The TT-303, on the other hand, despite being "circuit identical", can sound downright weird at times (as can Roland's other "analog modeling" 303 reproduction, the TB-3)
Here is a 4 way comparison of the 4 synths I just mentioned complete with waveform visualizations: