I am using all three variants (XT, Pro & LT) Not all in the same rig you understand

... Although am using the Pro & LT (LT as a slave device) in the same PC.
There's nothing else on the market that I know of that can do what these Aquaero 5's can do..
It can take a wee bit of work to get your head around everything these units can do as regards to monitoring & letting you decide how the cooling is applied e.t.c. but if you take it slow & read up on things before you go connecting all a-sundrie to it's various connections before you understand the basics, you'll be fine..
It's not too difficult with a bit of patience & learning, once you get it set up as YOU want it, It will just do it's thing in the background leaving you with peace of mind that should anything go awry with your PC (depending what alarms you set) this unit will warn you, or shut down completely (again depending on what alarms you set up) your PC & in so doing protect all your Preciousness you have in your case

...
All with the added bonus that you can make up charts to show either in the software or on your desktop of pretty much any sensor you have connected to the Aquaero, Be it pumps, Rad Fans or Air cooling fans, CPU & GPU die temps, motherboard temps, water temps set up various alarms to react as you want with warnings or complete shut downs e.t.c e.t.c..
For me personally, I wouldn't use anything else now & it's correct that the original software & firmware were abit hit & miss at the start, But this is now well sorted for most users now & the software is pretty damnded smart & once you get your head around things is fairly easy to set up.
There is a lot too set up though remember depending on what you want from the unit.
All the best
Nams