The module is very customizable but the parameters are all intuitive which makes configuration easy (there are some modules out there that "customizable" translates into "confusing"). Anyway, the one feature that makes this a "must have" for anyone using K2 is the ability to show a list of articles based upon a tag. Want to have a module showing a list of product demos? Just tag those articles/items with "product_demo" and enter that tag name into this module. Voila, a list of those items appears. No need to go back and modify the module when you add another item. Simply tag that new item with "product_demo" and it appears.
I had been using Extended Menu (mod_exmenu-j15) to accomplish this but had to enter in the item IDs explicitly in the module. This is a MUCH cleaner and easier approach.
One thing to note is to make sure you download the proper module if you use K2. Download "mod_dmk2articlelistpro". There is a similar module "mod_dmarticletitleslistpro" which has more Joomla article features but does not support the K2 tag feature.
If you are a K2 user then get this module. You won't be sorry. My thanks to the developer.