NAA has done extensive velocity testing and publishes the results, in 22LR, 22Mag, 32ACP and 380ACP.
To understand the data, you need to know that a Black Widow is always a 2" revolver and the MiniMaster is a 4" revolver.
Other tests over the years have shown that NAA's numbers in general are very honest. Even if you don't have one of their guns, this page is still a prime resource for mousegun ammo performance:
http://www.naaminis.com/naaveloc.html
You'll also find a table of bullet energies linked from there, or jump to it at:
http://www.naaminis.com/energy.html
This will tell you that a 30grain round doing 1,200fps has 96ft/lbs of energy and at 1,400fps from a 4" barrel, 131ft/lbs. You'll get even more from most Rough Riders or Ruger Single Sixes.
The 32ACPs out of Guardian/Kel-Tec class barrels, are generally around 70grains pulling 850fps for 112ft/lbs energy. The hottest involve a 73grainer at 900fps, for about 130ft/lbs.
So out of a Rough Rider, Ruger or MiniMaster, the 22Mag is clearly in the same ballpark as the *best* 32ACPs, better in the 6" or longer tubes. In the Single Six 9" barrel, guesstimate 1,600fps and you're at 171ft/lbs - 38Spl territory. Even out of a 2", it's inside of the 32ACP performance range.