Bottom Line is unless you believe the lights are AMAZING, and you just have to have them, and are TRULY willing to take the risk on offering them to your clients in an attempt to earn your money back, and create a ROI with them then spend the money on the lights.
If you are just seeing other DJs use them, and the lights are essentially eye candy to you, then do yourself a favor, and don't bother with the investment because I can 100% guarantee you that you WILL NOT make the money back that you spend on this type of lighting. In this scenario, the lights are essentially a new toy for you, and a year or two, or maybe 3 years down the road if the lights last that long without breaking they will eventually become unused paper weights collecting dust and you will want to get rid of the lights, and realize you never made money from having the lights.
In most markets with 97% of clients...you won't find clients willing to pay more to add this type of lighting in. You will find yourself using them at your events just to get them used, and pretending that the lights are upping your image/presentation at your events. If you are completely fine with dropping the money on these lights in this scenario, then buy them. If your goal is to have a ROI on the lights, and will not be happy if you don't earn your money back, then save your money unless you love taking a lot of RISK.
Just my 2 cents. Good luck with your decision.