POV lighting is a contentious subject that is pretty much frowned upon by the members here. I'd suggest you take a gander over at elightbars.org.
Some thoughts I posted on another forum:
Why
When it comes to installing lights on your vehicle, the first question you must ask yourself is this: WHAT DO I NEED THE LIGHTS FOR?
I know all of the rote answers, but I challenge each and every person that is thinking about installing lights to take several moments and think long and hard about this. Ultimately, it will be your decision but there are several factors you must consider and I will try to address some of these.
Laws
Next, you need to check out your state's laws concerning vehicle lights. All states limit what color you may use (amber is generally a safe color choice) and some states even restrict what lights may be placed on the vehicle. Some states also limit when the lights may be used, and some even have further restrictions concerning visibility and coverage arcs. For example, in my state of Washington, ALL vehicle lights (including amber) MUST be approved by the state patrol (ref
http://apps.leg.wa.gov/RCW/default.aspx?cite=46.37.320)
Also, if you plan to cross state lines, make sure you are aware of the other states laws concerning vehicle lights too. Just because your legal in your state doesn't mean that you will be legal in the next one.
Liability
Bet you didn't think you would have to call your insurance company before you put lights in your vehicle, but this is important. Some insurance policies have clauses where they won't cover your vehicle if you perform modifications to your vehicle's protective systems, even if your adding to them. Adding lights increases the load on your electrical system, and therefore increases the risk of shorts, fires, and other problems. In addition, your insurance company may want to charge you higher premiums because you're now using your vehicle for something that is higher risk than normal everyday use. If you don't think it's that much more of risk, then why do you think you need lights?
Also, under liability, I'm going to take a moment and address the use of arrow sticks. THESE ARE A BAD IDEA for POV's. Simply put, once you use these, you are in effect directing traffic. This may be illegal in some areas, and legal in others. Regardless of the legality, you may assume the liability for directing traffic. What this means is that if you have your arrow stick going to the left to move traffic to the left, and a vehicle gets into an accident because of your traffic revision, you may be financially liable for the damages.
Coverage
It seems like most people forget that they need to protect their vehicle from every direction. Just because headlights and taillights cover the front and the back, doesn't mean that you can ignore side protection also. This is what makes the hide-a-way systems like taillight/headlight strobes, arrow stick, and lights on the dash a bad choice. They're great for front and back protection, but offer very little if any side protection.
Quantity
How much is too much? This is a case where less is better. A single rotator or strobe, positioned on the roof will offer better coverage with less current draw than having a full blown police package setup inside of the vehicle. In addition, this will allow you to be seen without affecting or distracting the other drivers that you're worried about.
Location
I covered this briefly earlier, but am going to expound on it here. Where do you put your lights? Low profile and hidden lights are great when they are not being used, but suffer some visibility problems once they are turned on. Any light that you have on your dash or inside of your vehicle will reflect across your entire windshield or rear window, and seriously affect your visibility while driving or spotting.
A full blown lightbar, besides being expensive, is generally unnecessary and can be a bigger distraction than you realize, to you and other drivers. A full blown external lightbar has a multitude of switches and generally requires a full switch panel to effectively operate.
So what is the best balance between the visibility of an external light bar, and the low profile lack of attention from hidden lights? Simple, a light that you can mount on your roof when needed and remove when not needed.
Types
LED's, strobes, and halogen...which one do you choose? Each has their advantage and disadvantage.
LED's are the new fad in lightbars, and in my opinion, aren't all they are cracked up and hyped up to be. Yes, they are very bright, but only if you are looking directly at them. They don't reflect off of other objects the way strobes and halogen do. This makes them very good for rear protection (such as brake lights and turn signals) but not so good for front protection. In addition, while their bulbs last longer, they are more expensive to purchase and repair if something goes wrong. On the up side, they draw less current that strobes or halogens.
Strobes are the best at attracting somebody's attention when they aren't looking directly at you. The down side is that they can reflect back and affect your vision more than any other light. They tend to draw the most current, and often times require a seperate power supply for them. In addition, replacing bulbs in not always a cheap proposition. A single external strobe can provide simultaneous 360 degree protection when it flashes.
Halogen rotators have fallen out of favor because they aren't as flashy as strobes or LED's, but they are the best bang for your buck. Bulbs are cheap and easy to replace, they have a moderate current draw, and generally don't require a seperate power supply. The draw back is that the rotator can only protect you in the direction that the mirror is facing, which means that while it will cover 360 degrees, it doesn't do it at the same time. There is a time lapse as the mirror rotates the 360 degress.