There is nothing cheap about doing a proper LED setup. The Lumileds and Cree P4 I used were something like $.30/each. I used approximately 500 of them for both sides. Include the boards, wiring, resistors, PWMs, regulators, and any other incidentals and you're looking at $300+. This is of course an S4 setup where I used an extreme amount of LEDs, but it is still not cheap regardless.
I would also not suggest skimping on cheap LEDs for tailights. Cheap LEDs don't hold up to heat nearly as well and in a taillight application where you might be standing on the brakes at a stop light for a couple minutes, heat is an issue. LEDs may last 10,000 hours in perfect conditions, but add heat in and that drops dramatically quickly. On top of that, heat causes a shift in the color spectrum that is usually less than desirable. In addition, I doubt a cheap pre-made ring is conservatively run because the need to up the amperage for increased luminosity from cheap LEDs. For the Lumileds that are rated at 70mA and you run at 50mA for a nice bright light, it's no problem. However, a cheap 50mA run at 70mA isn't going to be happy. Now for interior LEDs such as dome lights, I wouldn't have any issue using the crappy chinese LEDs on ebay. Even if their life expectancy is cut to 50 hours due to overrunning and being cheap, that's probably 20x the amount you'd ever use your dome lights.
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1986 Sport: 132k miles, 5A (Sapphire Blue Metallic), Tokico Blues, Racing Beat Springs, Custom LED tailights (only S4 LED tails in the world), SSR Mark II, Racing Beat exhaust, S5 black interior, Rotary Resurrection rebuild at 120k miles
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