Hi folks,
I'm looking for a free or inexpensive twin engine verb VST plugin.  Do you have some helpful input on this subject? OR direct me to a previous thread on the subject?
 
Thanks.

IR Convolutions reverb. There are no other way to go if you want quality 100% realism.
The IRs of hardware's and real places can be downloaded for free on many sights over the internet. Do a search.
 
http://www.liquidsonics.com/software_reverberate.htm

MickyD
I'm looking for a free or inexpensive twin engine verb VST plugin.

What do you mean by "twin engine"?  2CAudio's Aether has two internal, independent engines, one for early reflections and one for reverb tail.  Their B2 reverb has two independent engines that handle both ER and tail.  Neither of those are what you'd call inexpensive (although the quality is very high, so I'm not implying they are overpriced).  But is either of those features what you're looking for?