The Monsta is merely a thicker version of the Alphacool Nexxus series for which reviews abound. You'll note the the 60 mm version tops the charts from 1000 to 2200 rpm.
https://martinsliquidlab.wordpress.com/2012/04/12/alphacool-nexxxos-ut60-360-radiator/4/.
The Nexxus is n excellent radiator with screw protectors, 7 connection ports gives it great versatility. Ne Nexxus comes in 30mm (ST), 45mm (XT), 60mm (UT) and the 80mm thick Monsta. One thing you will notice if that you don't get a lot of extra cooling with increased thickness ot normal fan speeds. To get any benefit from the extra thickness, you really have to get into the well above normal fan speeds which of course means more noise. I have multiple Nexxos rads and I limit them to 850 rpm on 1250 rpm fans (Phaneks F-140SP) where they are dead silent.
Here's a radiator sizing guide thread and download link. You will nbeed to sign-in / register to use the download function
http://www.overclock.net/t/1457426/radiator-size-estimator
http://www.overclock.net/attachments/19911
Here's the Stats on a single 140mm if radiator with one fan in a push configuration
At 1000 rpm, the 80 mm Monsta gets you just 2 more watts than the 80mm Monsta
ST30 68 watts
XT45 68
UT60 69
Monsta80 70
At 1250 rpm, the 80 mm Monsta gets you just 2 more watts than the UT60
ST30 82
XT45 83
UT60 85
Monsta80 89
At 1400 rpm, the 80 mm Monsta gets you just 6 more watts than the UT60
ST30 90
XT45 93
UT60 95
Monsta80 101
At 1800 rpm, the 80 mm Monsta gets you just 5 more watts than the UT60
ST30 110
XT45 117
UT60 122
Monsta80 127
At 2200 rpm, the 80 mm Monsta gets you just 18 more watts than the UT60
ST30 127
XT45 139
UT60 148
Monsta80 166
The above results will obviously be affected by push / pull where air flow rates will increase from 10 - 30 % depending upon the fan. Because of the low fpi, high static pressure fans don't really help. The 5 watt difference between the UT60 and Monsta for example, jumps from 5 watts to 7 watts in P/P.
As you can see, only at the extreme 2200 rpm speed, is there any significant performance boost from the Monsta. Case wise, my "go to" rad thickness at the top is 45mm (XT series) for motherboard clearance and the 60m (UT series) on the bottom. Again, for noise reasons, Id suggest not using anything faster than 1250 rpm fans. At that speed, the Monsta gives you just 7 watts more then the ST30. At 1000 rpm, it's just 2 watts. So, set up to run at a dead silent 850 rpm, there's mo discernable advantage from a heat removal standpoint to use an 80mm over a 30mm.
Are there any other advantages / disadvantages ?
- Size and fit are obviously an issue. Fitting the rad at the top of a case is a challenge in most instances.
- The radiator is larger than means buying / mixing 33% more coolant than a 60mm rad or almost 3X that of a 30mm rad.
- The greater volume of thermal mass gives you extra thermal mass which will help equalize and spikes in heat load. I doubt you would be able to physically measure the difference tho.
While construction wise the Nexxos series is right at the top, their cleaning methods leave a bit to be desired. Alternating flushes with acid / base solutions must be done as a minimum, followed by tap and DW flushes. However the use of the Mahems Blitz Kit is highly recommended.