Ordered a set of these for my 2000 4.0L Cherokee. Excellent service, got back to me within hours. Order process was simple (PayPal) and the product was great. I had an issue with one injector, the owner sent me a replacement set at no charge for the product or shipping! Stellar service if you ask me.
These injectors increased the off the line power (feel) and the seat of the pants experience says I have more HP to play with now (likely same HP but available sooner). For less than the cost of a Fuel Injector service at any shop, these are almost a no-brainer.
I would rate this upgrade a solid 10 out of 10 for service, delivering on promise of improved performance and I am getting slightly better MPG as well (marginal).