D'you mean the multi level cages or the single level ( I looked at 120cm cages on the Zooplus site)
I have an indoor 4'x2' ( I'm old, I use imperial 
) which is the same length , I would ideally like a larger cage but they just sleep there in winter.
I saw some really big (and ££) cages in Jolleys , aimed at rabbits.
The depth of the plastic base to stop them kicking out their bedding (I'm using wooden pellets to give a soft base then on their sleeping side newspaper and shredded paper or a piece of fleece. This all gets thrown out daily)
There's not alot of room with two food bowls TBH.
Mine wouldn't use a ramp so I wouldn't buy a 2 level (and I'm not sure how secure the 3 level ones are) the ramps are steep too.
Can you post a photo of the one you are considering?
Plastic base is easy to clean though. Spray/wipe. But it's hard plastic and my lardy hogs appreciate the softer wood pellets.
Ours live in the small bedroom, we put a couple of fleece blankets over the top to insulate them (and convince them to go to sleep ) 