Help picking a new tank

[SaltlifeHokie]

I've been doing some research the last few days and have somewhat narrowed down what new tank I'm going to get and was hoping for some feedback in the individual ones. My plan is to get a smaller tank 40-70G+/- to start with to gain some experience with. Ultimately I'd like to get a 180+/- tank so I'm essentially starting with my "2nd" tank so therefore don't want it to be huge and take up space in the room for the bigger tank later. I've had saltwater tanks before but still fairly new to the hobby and figured I'd start a little smaller and not spend as much money out of the gate at first. I was hoping someone could help lead me in the right direction between the following tanks.

IM SR-60 NUVO PRO 2 AIO
Red Sea E-170 LED Complete Reef System 45G
IM 40 Nuvo Mini Fusion Lagoon Pro 2 AIO
IM 40L NUVO Fusion Pro 2 AIO
IM NUVO EXT 75G Complete Reef System
Red Sea XL 300 G2 65G

 

[theatrus]

I’d personally lean IM tanks, but a lot of what you’re deciding on is personal choice. There isn’t a right answer.

 

[SaltlifeHokie]

I'm thinking either the IM EXT 75 Gallon tank or the SR-60. What is everyone's opinion on AIO vs Sump

 

[SaltlifeHokie]

It’s looking like a sump is the better option. Anyone object to that thought?

 

[theatrus]

Sump, if you can manage it, is always preferred.