Hi Ezz, I can't answer all of your questions, but I will try to help! I sell pre-loved baby goods so I have seen a lot of portacots come and go. I find Steelcraft make a great portacot, they seem really safe and sturdy and lightweight. Also Mothers Choice and Babyco (their own brand) are great ones that aren't too expensive. I don't know how they rate with Choice, but I think they are pretty good.

The bassinette attachments are usually only suitable for up to 6-8kg so it is worth checking the recommended weight before buying one. I have an Esprit portacot which I love (though it is fairly heavy) and I naughtily still use the bassinette attachment because I have a bad back and it is easier for me to reach my DS in it.

I have never seen a portacot with side rails that come off to be washed, they may make them, but I have never had one come in. They usually get grotty from where you put your hands to set up and put down the sides so I suppose you should make sure you have clean hands before using it! Also, if you pick a dark colour it won't be as noticeable. I take portacots outside and wash them with warm soapy water and let them dry in the sun.

Anyway, sorry I'm not much help in answering your safety questions! I thought I'd just give you my personal opionion. Best of luck picking one you are happy with! (Don't forget you can actually hire portacots if you don't want to buy one )