my understanding is yes...unless specified in formation restrictions..as most formations are built from a certain codex...but i could be wrong
eg. the storm wing...the stormraven can be used as a transport for codex units that have the stormraven entry
im not to sure about the stormclaw.
eg. the storm wing...the stormraven can be used as a transport for codex units that have the stormraven entry
im not to sure about the stormclaw.