I have not used this particular system. I have used bar joists for roofs. Be aware that vibration can be a problem for bar joists with a thin concrete deck in the 28' span length range. Partitions, furnishings and thicker concrete can dampen the vibration.
This may be a great system to use. By the way, bar joists are usually so hard that drywall is not screwed directly to the bottom chord. On my project, we bolted 2x4's to the bottom chord and then attached the ceiling drywall.
Have you looked at Metwood Building Solutions: www.metwood.com This system uses a softer metal that will accept screws. The structural engineer at this company can stamp and seal the plans to meet the code.
I do not sell any products. I do donate a lot of time to interesting projects.