Great, that appears to be 12 MBits/second (2x 6,06 MHz) in comparison to the 480 MBits/second in the measurement i made on a CM6631A audio interface. You used cursors to determine the bit rate using two bit intervals, while i set a measurement gate to let the scope determine the frequency within that gate. And i could extract two different zooms, each one with its own gate and measurement.
It appears those scopes serve to derive the bit rates and the Rigol is good for full speed USB, while the Lecroy WR64Xi does USB2. This example is a bit silly anyway, since none of both scopes decodes the data. Don't know whether Lecroy offered this for the WR64Xi. We have a Lecroy SDA 6020 6 GHz scope that does it and puts the results into a table.
Risetime in your Rigol measurement seems to be about 80 nsec. Is this real or is that a bandwidth limit of the scope or the differential probe you are using? What is the input capacitance of that probe?
Regards, Dieter
PS: I guess it is real, because the differential logic amplitude is about 6 or 7 V, so it's an unterminated transmission line with the risetime determined by cable capacitance.