Silicone or rigid? I had the original Apple rigid back cover and smart cover but it was so heavy it made the thing feel like lugging a 13” laptop around. Plus the original Apple cover developed cracks very quickly so I returned it and got a clear thin plastic back cover on Amazon that served weil for a few years.I’m still really glad I use the first gen 12.9 apple silicone back with my 2nd gen
Flash is blocked and a mic, but non issue for me
I cant imagine ASK without the silicone cover too, and i dont think an amazon case or tpu back would be quite the same, protection or feeling or aesthetic wise