Well I don't have the 115 but I have a close equivalent in the 110i extreme by corsair, not even sure there is much if any difference between the two. Both are 280 mm AIO's not sure if pump or rad or much of anything is different...not sure what the static pressure on the fans I have are but they are 140 mm x 38mm so without even looking at specs knowing they push ton of air I'll be the static pressure is very high.
https://www.newegg.com/Product/Product.aspx?Item=N82E16835220056
looking at the specs and how they are advertised they brag about the pressure/cfm etc which isn't surprising 175 cfm is a lot for a 140 mm fan and it doesn't scream like the delta 120 mm ones do even full blast. I have 2 of these on my h110i and highest temp I ever saw was 78 degrees which was since I reinstalled it I don't think I did great job with paste spreading etc I'm going to have to check it and see how good the contact etc is. Anyway even that for a 3960x @ 4.6 ghz and 1.4 volts with high volts on Vccsa and Pll voltages for memory etc with HT enabled I think is near as good as it gets for intelburntest with corsair AIO as specced.
And I'll reinforce them with my experience this is my first ever AIO and even with 3 fans on my D14 as you were mentioning Kanan I can tell you this CPU just pushed it beyond what it wanted to cool...was struggling to keep it under 80-81 celcius with any stress at 4.5-4.6 depending on voltages and how hard I was pushing memory...at any rate, I can tell you temp problem essentially is all but gone for my OC now with this unit. Old OC was barebones 1.36 volts or so and that was causing 80 C readings now even newly applied with 1.4 volts and same CPU speed I saw it hit 78 and was disappointed lol. It really is night and day, I had 3 high cfm fans on the D14 too, 80-140 cfm. Didn't try it with the silverstone fans which I'm sure would have shaved a bit off but no way that would account for the big difference I'm getting with the AIO.
Nice, can only imagine how a 360mm rad would perform.