MaxIC

Hello all, I operate a small electronics fabrication/repair shop. We do hand soldering for the most part. Our products range from simple power supply circuits to amplifiers to controller boards with lots of ICs. Recently, we have had more and more people asking about when we were going to go lead-free. I didn't tell them this, but I really had no plans to do so until the United States puts a ban on it, which isn't any time soon. Good old 60/40 is what we have always used. But with more and more about lead-free, I seem almost obliged to make the switch. It would also be great as a marketing tool and would hopefully reignite some interest in our products. So I have a few questions. 1.) Any brand in particular for Pb-Free? (I am thinking Kester right now) 2.) What ratio of material is best? 3.) Is 2-4% silver worth paying for? (Usually about 2x as expensive as Sn/Cu alloy) 4.) Any changes having to be made with the soldering irons? If you could answer any of these questions, I'd appreciate it. Thanks a lot.