...... pffft, monopod instrumentation. bah.......
In regard to the handling differences you mention, and regardless of the known mods on the 91, is that based on taking all 3 cars through the same bits of road to literally compare, or is it based on your perception of what felt like it was handling better?
I ask because the non-PS models can feel a bit heavier in the steering than the PS models (obviously) but that doesn't neccisarily mean it's handling is at lesser level, only that one is easier to steer than the other. (psychological thing: easier to steer = better handling, otherwise it would be hard to steer

)
In a perfect scenario you'd use the same stretch of road for all test drives, and ideally be allowed to push a bit closer to the envelope than what a usual 'cruise around the block' test drive would consist of.
All that aside, as Enrique said, upgraded suspensions will (generally, unless they're really poorly executed) out-do the stock stuff by a pretty fair margin so it may boil down to more of a case of which body style appeals to you more and whether or not you really want power steering.
Beyond that, you can always do alterations of your own at your leisure to get things more in line with what you think it should be like.