I find them far more enjoyable with voice acting.

The only reason the older titles didn't have it was because of technical limitations.

Oh, and I tried your experiment. It's just as endearingly awkward with the text and without the voice. Still more enjoyable with the voices though.

X's voice acting had it's moments that were...less than stellar, but for it's time it was a lot better than most other games at the time, and by today's standards, it's still not terrible. If you'd like to hear some truly bad voice acting, just look up any of the Dynasty Warriors games from the PS2 era, or Majin and the Forsaken Kingdom for this generation.

XIII and XIII-2 both have fantastic voice acting. There's just moments where the dialog could have been better written. :P