Hi just noticed this free plugin and was wondering if this idea would actual be a good use for it..
 
https://www.plugin-allian...ns/detail/bx_solo.html
 
i) What I want to do is to check during the mixing and mastering process the audio tracks as a mono signal.. can it work?
 
Having played around with it seems possible to check also the M/S output..
 
ii) Are there any other plugins which do the same?
 

The Channel Tools plugin bundled with SONAR will do everything that one does, and then some.
 
To check mono-compatibility, just click on the interleave button on the master bus and set the interleave to mono.
 
What plugins such as the brainworx one are good for is comparing what parts of the mix are going up the middle versus sitting out at the sides. That'll give you an idea of whether your mix is wide enough, and whether the low frequencies are in the center where they're supposed to be.

Thanks Bitflipper - clear and handy tips. Cheers.