Whether you'll be affected by the smoothing applied in mice based upon ADNS-9800 is absolutely down to you as an individual. Most people will probably still consider it usable or, more likely, not even feel cursor "floating" caused by the inherent algorithm.
You really won't know until you try. I tried about ten mice in the last month, as I am attempting to find a new one, too. Acceleration in ADNS-9500 based mice was absolutely no issue for me, especially Sensei RAW still felt perfectly fine to me.
Corsair M65 and especially Logitech G500s dragged behind quite notably before being updated, after installing the newest firmware versions they were usable. ANDS-9500 and ADNS-3090 variants still felt somewhat "better" to me, although I could not physically pin down, why.
I would suggest you to order whatever you are interested in. For the most part, I think, ergonomics are the most important aspect to consider. Whether you will be satisfied by the way the mouse reacts to movement and the feel the sensor provides, is something nobody will be able to answer properly.