Below are some difference between Oreck 2100RHS and U2200HHS, hope this help.
Oreck U2200HHS vs 2100RHS
images from manufacturer

On/Off Switch Position
The On/Off switch of the 2100RHS is located in hand grip while the U2200HHS uses a Foot-switch Activation that has the control on base of the unit.

Cord Length: The 2100RHS has a much longer cord.
The 2100RHS has a cord length of 35 feet versus 25 feet on the U2200HHS.

Color:
The 2100RHS comes in blue and gray while the U2200HHS comes in gray and white.

Warranty:
The 2100RHS carries limited 1 year commercial warranty while the U2200HHS is backed by limited 1 year residential warranty, on oreck.com, the U2200HHS product page also indicates that it has 1 tuneup.

Similarities:
They are bagged.
Both have motorized brush roller, no way to turn off the brush roller for suction only.
Have side brush to clean baseboard and edges
No auto cord retractor.
No manual height adjustment.
Only a basic unit with No attachments, No hose, No cleaning wand.
No headlights.
Not self propelled.
Have only 1 speed.
Fixed handle, cannot be adjusted to fit your height.
No swivel steering.

If you know more similarities and difference between Oreck Commercial XL 2100RHS and Oreck XL Classic U2200HHS, please share below.