I haven't used one since I started with a straight, I do sometimes use a DE or SE and If I'm in a real hurry I'll use an injector I can get a passable shave with an injector in less time than I ever could using a disposable.
I do have a brand new unopened cartridge razor, but only because Gillette sent me it in the mail. I have no idea why, or even how they got my address.....maybe someone thought it would be funny.
The twin blade disposable hadn't come out yet and good DE blades were an arm and a leg. I saw a TV commercial for a Remington electric shaver and went the thirty some dollars for it. I had visions of one pass and BBS. I don't think I tried it more than once before it ended up in a drawer or maybe I tossed it immediately. A piece of junk AFAIC.
I've never tried a cartridge razor but when the Gillette 'Good News' twin blade disposable came out in the early '70s IIRC I began using those and continued with them until 2006 when a friend of mine found these forums and got me interested in DE and then straight razor shaving. Haven't looked back since.
I keep the old mach3 just incase but those electrics give me all kinds of irritation, and ingrown hairs on my neck. Which I hate but my wife enjoys digging them out'a my neck with tweezers and I hate because she calls me a sissy when shes digging and yanking. I will stick to my straights as much as possible.