if you pose your Death trooper in a museum style pose or keep the dynamic pose to a minimum you should have no issues with the rubber over suit break or splitting, the issues is after a bit of wear and tear from posing the plastic tends to split right on the seems, it doesn't deteriorate, unless there are other factors at play such as too little humidity , too much humidity, improper handling, taking the figures apart or undressing them (not all figures) (only certain ones) and after a few yrs of the older figures such as gammora, they started to add more polymers which allow for less chance of break down, its all about how you display and handle your figures, this will be a common argument however putting your figures in proper display cases using possibly a rowenta air cleaners helps keeps dust and other particles and pollutants , odors, etc.. from the figures, its best to use a non oil base leather,vinyl cleaner for the clothing as most are made from a fuax leather which consist of a fabric base, which is chemically treated with wax, dye, and sometimes polyurethane for both color and texture. they use either P lather or other materials like bocaflex etc.. these materials are extremely durable and should last literally yrs and yrs without issues unless a lot of handling is done, also if you do handle your figures often with fuax leather costumes or rubber its best to either was your hands well first or rub them clean with a dry cloth after, you'd be surprised how damaging our own oils that secret from our fingers can be.
i apologize if i sound like a know it all but I am in the middle or finishing up a book on 1/6 collecting and 1/6 figures and have learned so much about materials which ones are used, why, for what reasons and when, so on and so forth, a lot of behind the scenes interviews with painters, sculptors, material selectors, even with poly stone and why it was so widely used smart move for jabbas throne, not so smart for tauntaun but either way the book has so many chapters about likeness licensing, sculpting, production, pieces that have been shown but went poof into the night, the whole where are they now type pieces like the falcon cockpit etc.. it took a lot of time, effort and energy to get access to certain companies behind the scenes a lot of travel and a lot of research, it also explains the process behind the inception of an idea and seeing the process threw to completion and into the collectors hands and tells why figures take so long etc.. ive watched so many reviews and even you tube discussions from a lot of you tubers well known here in the forums and i started watching as a collector but after meeting with and speaking with people responsible for the processes at these companies these guys having these discussions specifically danoby2 and his counter part my goodness are they so far off and misinformed your basically getting personal opinions and literally about 1% facts. this only refers to when they discuss re issues market prices, delays etc.. but that's enough of a rant i will soon be posting details on the book soon as i need to add a bit more features specifically with collectors but it has helped me learn and understand more about the figures we collect and the materials used and what will break down what wont and why.. hope it helps.