For starters, check out the Litegait.com website under the section Research. The first four of the article summaries on this page are studies which utilize the LiteGait.
I believe the LiteGait system is the best BWS environment for my patients, and having 4 points of control allows for maximal support. The research being done, however, seems to use systems similar to the Biodex, where a single rope connects to a T-bar, allowing for much less control over movement. Does anyone know of research that specifically uses the LiteGait system?