I was a Sensor shaver since the mid 90s, and probably would still be if the quality of the blades and cartridges hadn't begun to slip, as prices continued to rise. It was that combo which got me mad as hell and not gonna take it anymore - for which I'm now much happier than before. Shaving was a drudge before, now a pleasure. I'd tried later models: the Excel, Machs, Fusion, but none of them ever attracted me. Even the tri-lipped latex hair-raising strip on the Excel didn't work for me. I found they got gloopy fairly fast. The more blades, the less control and ability to maneuver in tight spaces and provide detail.
I vote for the Fusion. I used to cut myself up pretty good with carts and the Fusion was the first one I got a comfortable shave from. Of course I had no idea of blade angles etc. so the pivioting head on the Fusion saved the day better than the other carts I tried - and there were several over the years.
With my current technique, I have no idea which cart I would like best, but I have no intention to find out as I am getting great and economical shaves with the DE. Economy may fly out the window if I buy the Titan R1 I am really liking the look of, but you get the idea...
I thought the Sensor was the best of the cartridges when I was still using them. Good shaves, small enough to be workable and less expensive than the higher blade count carts. I went from 2 all the way up to 5 blades and then back down to 2 trying to reduce ingrown hairs, but I had to go to single blade to make a real difference. I'll still use a Sensor Excel for cleanup at times in areas that I know I can shave closely and not usually get ingrowns, but as I get better with the DE I find I'm using it less and less.