It depends on what you are retrofitting. I did 450ea. MR-16/ 50 watt halogens with 7 watt (I think) Cree led MR-16's and the ROI was @ 5 months and the rebate paid $10.00 per bulb and at that time, about 2.5 years ago, that was half of the cost. I just looked before this post and the power company is still offering $10 per bulb up to 75% of Ttl. job costs and the bulbs have dropped significantly in price. I am and end user so I get the "price shock" that most folks have , but in many cases the ROI is worth it.