Deciding which Echelon bike to get

I don't need to have a screen, and I don't know how much I'll use the any connected app. I will often read or be watching something on tv or having a conversation while riding.

I'm looking at this model at Sam's club which would come with 90 days free of the app, and is the lowest price option at the moment.

I see a lot of other models discussed here that aren't available on the Echelon web site. Is there a reason I wouldn't get the basic Connect GT+ and would instead want to get the EX-4s+ or the EX-5 (I understand this can synchronize the resistance with an app).

Some other things I care about:

• not taking up a lot of room
• being able to move it (roll from one room to another, no stairs)
• I'm okay with assembly being difficult, as in time-consuming, but want to make sure that it will assemble well (not difficult as in, if you don't get one thing just right it doesn't function well)