There's different designs on the ML240L AIO's. The ML240L is the 'lite' version, so if a corner could be cut to save a little on production costs, it got it. Smaller tubing, less powerful pump, older pump generation etc. It's the cheapest and most unreliable, and lowest performance model. Equate it to a 4cyl Ford Mustang.
Above that is the ML240 which didn't have as many corners cut, but still isn't a great performer. 6cyl Mustang.
On top is the ML240R, which has the larger tubing, better flow, stronger pump etc. It's what the ML240 class cooler should have been all along. 8cyl Mustang GT.
Honestly, neither of your choices are great, the aircooler isn't any better than the stock cooler, and the aio (I prefer liquid coolers) I'd not...