I'm not sure if it's "better" now. But it's definitely one of the best Rollers in the game. The support it provides is absolutely amazing, and its range is absolutely redonk for such a strong weapon. The speed of recovering ink after a flick is VERY much noticeable though.
I'd recommend running it 9 out of 10 times to be honest because the amount of time it takes is SO long. You thought Splash Wall took a while, at least you can attack immediately after and have a shield. Dynamo has to either run away or some how miraculously get enough Ink back and flick again, all in a VERY limited amount of time, to kill whatever is coming.
I mean, in its defense, it should never be in the front lines, but sometimes close combat is a pain. It's a damn good Roller, but I'm not entirely sure it's quite the "best" one. Not after the nerf at least.