+1 on pass on the shocks. Most importantly because they don't really work, they just sound like they should, which is enough, apparently, to sell them to the unsuspecting customer, which included me back in the day. It only took me one or two trips to know I hated them.
In my observation they don't doing anything about the so-called shock. My apologies if this is already old hat to you. But what they do actually do is decrease the stability when you need them most. If you think "shock" is an actual issue for you perhaps take a look at the way you are using them. The "correct" way is with you wrist going through the bottom of the loop and your hands wrapped loosely around the upper straps and the handle. Using them this way the force is transferred through the strap and NOT your grip. Your grip will normally be used just to lightly "steer" the poles with the fingertips. When you are using them this way "shock" is not an issue for most people.
Also when you use them that way you will seldom want to use the extended grips - better to re-size the poles. You can still grab the poles further down with you hands in a pinch, but it will be hard to go back to the "death grip" method of using the pole, even for a short time, once you have use the straps correctly.
The other downsides are that the shock ones are heaver, more expensive, more parts to break, and lastly (the worst for me) noisy as hell. squeak, ping, pink, squeak, squeak. Even if you get rid of the squeaks and ping there is still a ringing from the springs.