I bought the InstantPot Duo 7-in-1 (6qt) a month or two ago and like it so far. I've only used it a few times...made yogurt (but my yogurt maker machine is easier), cooked dried beans, made vegetarian chili, and last night I made vegetable stock from veggie scraps. I have a whole chicken I plan to cook in it to use for several meals but it might be a day or two.
They are extremely safe to use (mine has different functions so you can use it as a slow cooker not under pressure, saute, etc) with multiple safety precautions in place. The biggest adjustment for me is the shape of the insert...it's like a big pot versus an oval shape of my old slow cooker so I think a whole chicken might have to sit upright in it. Not a big deal, just different. It is annoying having to clean several pieces on the lid (gasket, metal cover thingy, and lid) but there's no way around it.