I only went from a g27 to a csw 2.5 but I also had a ts-pc for a week and drove t300 and dfgt from friends and a csw 2.0 when I bought a used rim.
I think what you need to find out for yourself is whether you want an additional layer of feedback (motion) and are happy with your wheel or whether there's something lacking for you with the wheel.
For me the csw 2.5 is the most similar to a DD wheel. The 2.0 comes close to the 2.5 but it just has too much static resistance (afaik DRI always at -5). Same for the csl elite (tried at a store) and ts-pc.
They are lacking the punchiness and the reduced basic resistance.
The problem though is: I know quite a few people who went from t500 to an osw and needed a lot of time to like the details and punch enough to be okay with the totally squishy feel when driving straight.
There's sadly, engineering wise, no way to simulate two tyres with caster angle wanting to keep the wheel straight with an electric motor.
An electric motor can only pull left and right. To program it to "work against any resistance from driver's hands" while still moving from the details of the ffb is extremely difficult and I'd almost say impossible since no developer did that yet.
So in the end a t500 feels "better" in some way. It has a high basic resistance, feels nice and beefy when driving straight but once the ffb kicks in, it can spin quite swiftly.
This leads me to the drift setting of the csw 2.5 although I'd rather call it "beefiness".
- 5 (max basic resistance) feels the best when going straight
- 1 (almost no resistance) feels the best mid corner.
0 is too light... And the positive values are garbage anyway.
So even with a csw 2.5 I still get to decide between squishiness and beefiness.
A friend of mine got the new simucube pro and he is still not happy after a month, upgrading from a t500.
Now the question is: would you like the details and punch enough to live with the squishiness or would you be okay with losing details and drive with higher electronical resistance set in the DD base?
I can only say that I really liked the feeling of the ts-pc.
But I always ran it at 100% and would've liked 150% of that...
With the csw 2.5 I often only run 70-90% base strength.
Your wheel is somewhere in between. Probably has good punch and torque, a kinda high base resistance but lacks a bit overall.
You need to think about this. Do you want more torque, more details but could live with a kinda "empty feeling" when driving straight?
Is that really worth it?
I honestly think adding motion would be the better decision. With my csw 2.5 I wouldn't think about a DD wheel and definitely get motion!
Only get the DD if you feel "not satisfied" anymore with what you get from your wheel like I did with my g27. It felt like an unresponsive, clonky, too weak mushy crap when driving around the track instead of driving a real car.
Case was clear!
Conclusion:
If you are happy with your wheel: get motion.
If you aren't very happy with your wheel: get a DD or a used csw 2.5 maybe.
Quite a long post for the content I actually brought into this thread but I thought a long time about ffb, motors etc.
I'm interested in how it works and what the wheels do lack and how to possibly improve them.
Maybe it gave you some input you didn't get yet