I am looking at getting a new set of trekking poles, and have questions about different features that I would like to hear feedback on.

Basically, I have a set of Lekis with shocks that are in fairly pooor condition due to use. I was looking at getting another set of Lekis to replace them until I started checking out other options, and the Black Daimond brand poles caught my eye. My expereince with the Lekis is that I like most of the features, but I don't much care for the twist style locking mechanism. The flick lock mechanism on the BD poles is very attractive to me. So, with that said here are the things I would like to hear feed back on:

1. For those that have used both the twist lock and flick lock style of mechanisms, what is your preference and why?
2. What is the difference between foam and cork grips (I know what foam and cork is, so what I am really looking for here are what are the advantages of one over the other)?
3. For those that have used poles with and without shocks, which type do you prefer and why?