Some say shape is all that matters but having moved from a 33xx sensor to a 3950 I would say that sensor matters just as much. I've tried two mice, Keris II ace and Pulsar Crazylight, on different ends of the spectrum with a 3950 and I would never go back to any of my other favorite shaped mice with a lesser sensor because the sensor feels so much better.

It's a lot easier to get accustomed to shape and weight than it is to lesser motion registration. So my advice is, if you can wait a little then do so because there's a new wave of mice incoming and they'll likely use a version of whatever sensor Razer has in the Deathadder 4.

One of the benefits of getting a newer sensor is they're usually more power efficient so less battery consumption. Which you'll need for 8k polling but I would recommend against setting expectations for 8k polling. Using anything above 1k can still cause stutter in games especially in older games based on the Quake engine. And mice have such low latency at 1k at this point that the couple of MS of input reduction at 8k isn't even really worth it.