i just moved from tucson recently. and let me say, that you may feel 20mph is slow.
BUT thats a small price to pay for NOT having to:
have a driver license
carry insurance
register (blinkers, brake lights, mirrors, emissions, etc)
ride out IN TRAFFIC....you have your own lane, a free pass up to the light during rush-hour

you have to be thankful for the freedoms you have. some states want the whole gamut (nearly impossible) before you're legal.

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