Skiplist / best practice for 2.1 branch

[Tim Pushor]

All,

Hello, and I must first apologize because I know that what I am asking 
has been covered before, but I am having a difficult time finding 
information in the archives.

I am still running the 1.6 branch on all of my production servers, and 
want to bring everything up to 2.1. I have resisted thus far for a few 
reasons, one being reported problems with Sleepycat DB (as well as grief 
trying to get all the software on my system to use one particular 
version of DB).

I have done some research on the skiplist algorithm, but am wondering 
about the cyrus implementation. Is it stable?

What is the current recommended/best practice for configuring 2.1.10? 
Which components should be DB as compared to skiplist?

duplicate? mboxlist? seen? subs? tls?

I definately favor reliability over performance.

Thanks, and pointers to relevant articles or past discussions welcomed.

Tim