For me the biggest difference between convolving reverb and the M7 remains twofold:
1. in some situations the Bricasti is just superior (with the right preset). It just sounds pretty amazing !
2. in other situations the convolving reverb (using my own samples) trumps the Bricasti, with one very big caveat. Although I have sold some of my samples to one firm (which does not exist anymore), I have to admit getting it to sound exactly right and natural asks -a lot- more from the end user then the basic presets/settings.
You HAVE to go in and tweak those early delays, offset and level to get something that really sounds better than the dry recording.
M7 = after 2 minutes you have an amazing reverb
convolving reverb can take up to 1h to get it right. If it still does not work, then M7