In reality a SS is so that you can shift into the proper gear before the RPMs drop below the speed of what the tranny will be once in gear. This is normally a problem in cars that have a lightened flywheel and the RPMs dance up and down like crazy. I find that I have to actually wait before I re-engage the gears to wait for the RPMs to match the tranny.
I had a SS in my WRX (factory STi) and I loved it. I hated having the stock throw. I also had to wait to engage the clutch between gears.
Don't get me wrong, SS rule and I'll be looking into getting one for my MP3 because I liked being able to shift casually without moving my entire arm, just my wrist.
Well, I guess the best thing to do would be to try as many as you can on other peoples cars and then go with the one you like. All SS are not the same! You may want to consider getting a new shift boot also while you're at it if you got the $.