After purchasing the complete edition of NIK Software plug-ins for Aperture 3, I have been learning the various programs.  I started working with ColorEfex and SilverEfex with excellent results.  The selective control points allowed for very precise control.  Here's one converted in SilverEfex:

SE - Custom - Painter, Santa Cruz, CA Natural Dam - Winter Moonlight

 

I appreciate the finishing borders as they offer an interesting quality to the image.  However, employing them crops the image by overlaying the border rather than adding a real border.  This reduction of image area can be fine, but I need to remember to account for it beforehand.

 

 

 

 

 

 

 

 

 

This BW image is a fairly straight conversion in Silver Efex Pro 2.  The original was a 3 minute exposure under a full moon on a cold winter night.  I am very pleased with these conversions.  The control points are extremely useful and the ability to group the points make it very efficient.  SE2 also has very nice finishing effects, including toning the image.  I have found sending the image to the Nik sharpening software prior to printing is a very nice finishing touch as well.    The prints from these images look fantastic.

 

 

 

 

 

And another enhanced using ColorEfex:

Corvair

ColorEfex has the control point ability but it is more valuable for the array of special filters that can change the basic character of an image