I found it unsatisfactory.
Repulsion field has a range of 9 feet. Melee range is 8 feet. Repulsion field ticks every .5 seconds. Base end cost of the power is .99 end/sec
What that means is that it costs too much for the mitigation it provides. The mobs will close to melee range and will get 1 melee attack in.
The subsequent mitigation is good though since it cost you no activation time and the mob is now KB'd.
Problem that I faced was with blasters I lost out on using my blaps too frequently and it's in force mastery so it's one of the least useful powers in that Epic. I couldn't really spare the power pick for a power that drained so much end and did no primary mitigation
For my controllers 3 melee attacks that got through would kill me anyway and I can keep an entire spawn at range for the ranged defense with my AoE Immob. It's in force fields though so it's cheaper to get the ranged defense since you get the benefit of Dispersion bubble. You also get Force Bubble though and can keep mobs at range from a much larger distance away. It's also cheaper in end costs.
It might work on a defender since you get no AoE immobs unless you are a /dark. I'm not going to bother trying though since it didn't work nearly as well as I thought it should for my controller and blaster especially considering the costs.
-Insanity is doing the same thing over and over again and expecting different results. - Albert Einstein.
-I do not feel obliged to believe that the same God who has endowed us with sense, reason, and intellect has intended us to forgo their use. - Galileo Galilei
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I'm picking it up on my En/En build, but more because it sounds like more fun than PFF on a guy that's all about Knockback (and because I want to get Temp. Invulnerability).
Still, it'll be a nice "get out of my face" power for when mobs get in too close. You don't want to leave it on all the time as it's an end hog, but activating it quickly when you know you're about to be mobbed (or need to make a quick exit) should be helpful. The same trick was nice on my Arch/Devices when he was in an enclosed space and surrounded: he just would toss out Cal Trops instead.
Guide: Tanking, Wall of Fire Style (Updated for I19!), and the Four Rules of Tanking
Story Arc: Belated Justice, #88003
Synopsis: Explore the fine line between justice and vengeance as you help a hero of Talos Island bring his friend's murderer to justice.
Grey Pilgrim: Fire/Fire Tanker (50), Victory
This reliable? When I build for ranged defence on a character, I try to ensure I can leverage it - usually with hover, or an AOE immobilize. Repulsion Field looks like an interesting possible approach.
Anyone got any experience wedding Ranged def with Repulsion Field?