I've never ridden an ebike. Care to explain the difference in practical terms? I imagine cadence and torque are roughly correlated, but with cadence sensors you'd have to pay more attention to your hearing?
I've really no idea, like I said I have zero experience with ebikes.
Cadence sensors detect how fast the cranks are spinning and apply power based on that, although I'm not super clear on where it detects the motion when integrated into a hub like this example. Torque sensors detect how much power you're outputting and apply power based on that.
With cadence sensors you can shift into an easy gear and spin the pedals and have the motor do all of the work, torque sensors add a percentage of your power and make it feel like you're riding a normal bike but are x% stronger. In general people that are already serious cyclists strongly prefer torque sensors but a well tuned cadence sensor can be fine on a utility type bike where you're not as picky about how the power gets applied.
Not sure on these ones specifically but the experience of a cadence sensor for me is rapid and unintuitive acceleration. In this way I think torque sensors, despite higher cost, are much more fit for regular non-serious cyclists like me.
Of course the comment OP should head over to a couple ebike stores and do some test rides to evaluate this and other factors for themselves if they're able.
I have very little experience on cadence sensors but have heard people discuss tuning them to be better. I don't want to poopoo something I haven't used and can believe that with proper software it can be acceptable for some uses.
Try a reputable bicycle brand mid-drive ebike at an expo or a store if you get a chance. You may not necessarily want that but it'll give close to the best experience an ebike can give.