I would be concerned about what the rubber bumps are made from (along with many other things)......I had those on some bed socks and they are easily removed by birds as my bird has picked some of them off, I was with him when he did it and I know he did not ingest any of them but I could easily see what he did with them.
I believe these tents make a lot of birds hormonal/nesty and can be the cause of territorial/hormonal issues but I would be much more concerned about the safety aspect given how many birds have met a horrible end with these items. There have been many birds loose feet or even worse their life from these sorts of tents/huts. You will need to make sure the hut has got no loose threads and this will need to be done each and every day.....if not many times a day. Threads are a big big problem for birds in many different ways.
Ultimately the choice is yours but I think you should have a look through this site for other stories of these happy huts/ bird tents so you know what main dangers they come with. No toy/cage accessory is completely safe but some have much higher dangers than others.