I don't think I've ever seen or heard of a cop checking a headlight for the "dot" markings... I've ridden with plenty of people with illegal equipment much worse than a non-approved headlight that was never mention when we were pulled over.
But really, why the hell would a cop check your headlights for compliance with DOT regs? I would just use whatever you want and wouldn't worry about it too much.
I had an acerbis headlamp system (SUCKED!) on one of my bikes which was illegal, I think it was even clearly marked "for off-road use only" and never caught any crap for it, for that matter my tires, taillight, turn signals (or lack thereof) and mirrors (or lack thereof) and no reflectors were all illegal.
Not to mention, its hard to justify pulling over a motorcycle because of a non-approved headlight (plus the LEO would have to establish a reason for the stop other than that, unless he can attest to being able to read 1/8th inch letters on the headlight of a passing motorcycle at speed) when I best ALOT of people here including myself are guilty of this one
42-4-233. Alteration of suspension system.
(1) No person shall operate a motor vehicle of a type required to be registered under the laws of this state upon a public highway with either the rear or front suspension system altered or changed from the manufacturer's original design except in accordance with specifications permitting such alteration established by the department. Nothing contained in this section shall prevent the installation of manufactured heavy duty equipment to include shock absorbers and overload springs, nor shall anything contained in this section prevent a person from operating a motor vehicle on a public highway with normal wear of the suspension system if normal wear shall not affect the control of the vehicle.
(2) This section shall not apply to motor vehicles designed or modified primarily for off-highway racing purposes, and such motor vehicles may be lawfully towed on the highways of this state.
(3) Any person who violates any provision of this section commits a class 2 misdemeanor traffic offense.
Source: L. 94: Entire title amended with relocations, p. 2267, § 1, effective January 1, 1995.
Or am I the only one who sees trucks with MAJOR suspension mods running around all the time?