Mini 5 since I had an iPad 3 before, so the form factor hadn’t been released at the time I bought it. I liked it, but couldn’t justify the money. I decided I wanted another iPad in 2018, so it wasn’t certain at that time that the Mini wouldn’t be discontinued.
Mini 6 had the excitement taken out of it somewhat by the jelly coverage, so it was need to check if it’s bothersome/noticeable to me rather than I must have this now.
iPhone 4 also (my first iPhone.) It had been out for 6 months when I got it but the store had sold the last one they had earlier that morning, so one from the next day’s delivery was reserved for me. They said they’d phone when it was in, so I was waiting for the phone to ring all day. In the end I went along to the store having not heard from them, as I wouldn’t have got there by closing time if I waited any longer to hear. It was New Years’ Eve and the phone was there when I got there, thankfully.