I used to have Guineas... I had a trio of females and they were in
this cage. It was small for them (they got exercise time in a large pen each day) but I was going to expand it with another unit, which you can attach either in a "L" shape or make it twice the length... A couple notes about this cage though... You need to remove the food / play area divider and also even if you buy the one with a top, this cage is not very sturdy to prevent predators from getting them, so if you have a dog or cat, this cage must be kept in a room they can't get to. One of the big pluses was that it does not require tools to assemble and it can easily be folded up and moved.
The cage was easy to setup and it was easy to clean. I used heavy moving pads (uhaul blankets) with 2 layers of fleece on top and it worked great. With litter trays under their hay area it was relatively easy to keep clean. That said, just know that GPs produce a TON of waste. I had to purchase a hand-held vacuum, which I vacuumed their cage and play area daily. The litter trays got emptied every 2-3 days, and the fleece got replaced once a week. All that said, they were fun, but a LOT of work. I ended up having to rehome mine (before I could expand their cage) due to developing an allergy to the hay they ate. I miss them, but they went to a good home with a friend of mine.