Cave Modeling Tester

Alright this is the first attempted at modeling the a section of the cave, this tester pieces will of course not be used but its to figure out the best solution to this problem. I've spent some time researching different ways and techniques trying to found the easier (in the terms of work flow) and most realistic way of making a natural cave system.
Current I have found two very different, very interesting ways of modeling the cave. Firstly is modeling the shape of the entire cave system by using faces/planes, this method is slow and complex. However the advantage is that once you finish the cave system, it can broken up.
http://www.hourences.com/tutorials-cave-modeling/ 

Secondly is by using a box the same length, width and height of the section of the cave your modeling and making the entire face of the cave out of extruded boxes. This method is faster is the terms of what you can modeling but takes longer to actually modeling the entire cave, furthermore compare to the first one it is far easier to actually get work done.
http://www.youtube.com/watch?v=JnnWNvvsP3s

The following images are a quickly made cave section (about 30 minutes) using the second method.