Confused by double hit. How does it work?
Someone like MMs are ostensibly the main use case intended for Radial. Because it uses the damage scale no matter what AT uses it, it should work out nicely for folks with very low damage scales. Masterminds and Defenders are the two ATs with the lowest scales in practice*, so it should work out well for them. Its other quirks, discussed in the rest of the thread, can mess with this, however.
* Controllers have a low scale too, but they can often get double base damage out of Containment, making whether Radial adds more than Core depend a lot on how good your powersets are at setting up Containment. On my Mind/Rad Controller, I believe actually get more mileage out of Control Radial, since I have a 70% chance to immobilize foes with my damaging AoEs - a dramatic improvement over having to rely on Mass Domination and Mass Hypnosis for AoE applications of Containment.
Blue
American Steele: 50 BS/Inv
Nightfall: 50 DDD
Sable Slayer: 50 DM/Rgn
Fortune's Shadow: 50 Dark/Psi
WinterStrike: 47 Ice/Dev
Quantum Well: 43 Inv/EM
Twilit Destiny: 43 MA/DA
Red
Shadowslip: 50 DDC
Final Rest: 50 MA/Rgn
Abyssal Frost: 50 Ice/Dark
Golden Ember: 50 SM/FA
Helps on Peacebringers and Warshades, too. Their recharge numbers tend to be low, but so does the actual volume on their attacks (low mod), and they tend to sit at the cap during league gameplay.
Have a quick question, take my MM for instance. My tier 2 personal attack gets a huge damage boost from radial making it go from 97.812 enhanced at lvl 50 to 167.14978 at 50 with radial. That makes the 2 tier attack worth taking now, yes? Heck that's almost double what my Assault Bot get's from his plasma blast damage with radial - 85.352, dual blast is 161.94266.