Welcome!
Sump systems are not complicated. They are more spacious and flexible than AIO tanks. It is very easy to add components as needed.
AIO tanks are limited in component addition. Though not as much as they used to be! If you browse through this and other AIO threads you'll see us treating these tanks no different than people with sump systems. Maintenence on the AIO is a little more difficult since you need good access to the rear sump for cleaning etc. still, not a big deal once you get used to it.
I believe the IM80 was discontinued but I'm not sure about the 60.
I'd say to do your homework and shop wisely, and get the biggest tank you can afford now...because there is no doubt you'll want to go bigger eventually.
That said these 40s are great systems. If you have limited space, they are near perfect.
Don't discount other brands either. Red Sea, JBJ, cad lights, etc all make AIO systems that are visually appealing and very functional.
Good luck in your research. Hope to see you back here with the 40!