I recently discovered the existence of a thing called a router lift, in answers to [this question][1].  I'm intrigued and would love to get one. 

A bit of internet research later, and I see there is quite a bit of variety, not only in price, but in basic feature sets.  

Assuming I would like to purchase (rather than construct) a lift, what features seem to be important to you?  For instance:

 - Do I need a "quick change" ring to facilitate bit changes?
 - Do I need to be able to lock the lift to a particular height?
 - Does a flex-shaft controller (that I can attach to the side of the router) work better/worse than a screw controller (that means I have another hole through my insert plate?
 - Others?

  
If it is important to answering the question, I have a DeWalt 625 plunge router (as long as my frustration with fine-setting bit heights hasn't caused me to throw it through the workshop wall).


  [1]: http://woodworking.stackexchange.com/questions/2196/is-a-plunge-router-suitable-for-router-table-work