Not a huge difference only working with 13 but you have a lot of citizens to work with. Worker, Homeless, Addict, Criminal(stat). Personally, it's not worth it to hold them unless they are fully utilized. When experiments dropped, I turned every SINGLE citizen without a tax refund into a sicko and I have no regrets. Some of those extra stat cards can be rare so you might want to check the market before converting them. If the stats aren't as valuable for farming extra assets as they are for farming SIM just convert. Artist and Scientist stats aren't nearly as valuable now as they once were, so you really have a lot of potential to grow with experiments. Just keep in mind that Sick Citizens have a negative income so the more you hold the lower your base income will be until it actually affects the tax refund stat.