REAPER supports VST plug-ins (up to version 2.4).

But obviously REAPER still seems to miss some features:

the reacontrolmidi plug in is vst 2.4, so I'm guessing the rest are too but as my main host is Cubase, I'm wondering is there Intellectual Property rights being excercised. Regarding Dstruct mention, does reaper even support delay compensation? I note it doesn't seem to support direct monitoring. The site looks good and the app looks fine but are some vital features missing?

thanks, but what about the synthesizer plugs, can I use them in other hosts or only the Reaper application

Thanks. All bar the reacontrol midi are 1.0 compliant and if you look on the steinberg website you'll note they are no longer supported.