Use of either depends on the application. Flexibility is normaly an issue. The more strands you have the more flexible the wire. Generaly in my experience solid is only used in 12awg or smaller and is specificaly stated in specs to use stranded for anything bigger than 14awg. Stranded will always pull easier in raceway. Solid will obviously push easier in many cases, but not all. Imagine trying to pull or push a solid 500kcmil. Never happen.
In industrial environements I have worked in, solid wire isn't even allowed to be used.
Agood book (tool) which every sparky should have is theAmerican Electrician's Handbook. It goes into specific detail on almost any question like this you would have.
Division 2 Properties and Splicing of Conductors.
