I put on the Woodhouse modified shifter and had a factory knob shortened by 1.5". Works great and looks pretty factory. The only gears to really pay attention to are 4-5 shift and 5-6 shift. They require a little understanding of suttle jog movements to get them right if shifted quickly. Good thing they are rarely used. 1-2-3-4 are very solid and not a problem.
Then again everyone has different arm lengths, heights and that all adds to how well or different you have to treat your arm in shifting. Practice can make any shifter the perfect one, though I did notice a differece with the set-up I put on.
At first I had Woodhouse engine and tranny mounts on and they did make it bullit proof for shifting, just in and out on every gear. It was very noticeable improvement. HOWEVER, it does let a lot of vibration and noise through the drivetrain and right into the interior. After install, I had plastic interior panels rattling, the rear view mirror was useless and it was shaking all the time. I took out the mounts as the comprimise for the best shift ever could not make up for the vibration issues. Maybe over time they would have gone away but I don't rack up the miles in my Viper and I was not going to spend the few I do, like that. If I was racing, absolutely would have kept them, but for the street and most non-racer drivers, they are not the way most would want to go. A bit too much. You would get use to it after a while, but do you want to? Not me!
Now when they had the tranny out to do this, I had them install a Fidanza Lightweight flywheel, which I feel was the biggest improvement of all (aside from 3.50 gears in the rear). Some like them and some don't but they really woke the car up as the response is greatly improved. Just my opinions however.