Dump the 5645's, they are more weight, not near as fast and less torque than the 5945 or the replacements that just came out which I think is the 5985's but the 5645's are cheaper. You could use the 5955 on the rudder but you really do not need it. I'm using 5945's all around and they are more than enough on Li-ION at 6V.

I'd love to have 5955's everywhere as my 5945's are getting sloppy again. Maybe some day they will come out with titanium gear sets for the 5945