Here are my personal experiences with Eitan:
Back in July, 2014, I ordered an Arcane 3W laser from him. Eitan was very responsive, and had all of the properties of a good seller: good customer service, relatively fast shipping for Israel (no fake tracking numbers, got here within 14 days iirc), and quality product (it still works perfectly now).
Recently, in Feb 2016, because of my good experience with him, I decided to talk with him about building a 16x 405nm laser. Many pm's were exchanged, and his response time exponentially increased. He would say how he will get me information I asked for (LPM graphs of diodes, etc) the next day, and I would wait for a week with no response. I would email him back, get a response that he would update me soon, and nothing.
Now that I have read through this thread, I am so glad I decided to just drop this completely. Dodged a bullet there.
Eitan, if you are reading this, know that I still think you are a good, albeit naive person. The world of businesses is very harsh. Your morals and beliefs do not matter. In order for any business to survive, you need to always have satisfied customers. You will need to make sacrifices. Don't think that your life is more important: that is a childish belief that does not work in the real world. If you want to run a business, the business IS your life. Everything else comes after. People are not forgiving, especially when it comes to their hard-earned money.
Do not let me down. Do not let LPF and the entire laser hobby community down. Take 24 hours, and enjoy them, as they will be the last 24 hours you enjoy for years, if you want to make this up. Think about what you have done in a detached, objective manner. Realize that you are the one that is wrong here. Pick yourself up, dust yourself off, wipe away your tears, and get everyone their money back. It is not the customers' responsibility to wait for you. Borrow from your parents, or take out a long term loan. Pay everyone back IMMEDIATELY. AFTER everyone has their money back, work off your debt separately, in your own time.
Whenever you sell something, it is your responsibility to deliver. If you fail, and your product does not meet what you guaranteed, the fault is on you, not anyone else. You need to make sure that every customer either gets what they paid for, or their money back.
Stop making excuses. Start doing something to pull yourself out of the large field of quicksand you jumped into, or you will only sink deeper into it.
To everyone who has not had their money refunded, I will repeat what InfinitusEquitas said: DO NOT close your PayPal claim. Eitan, and Eitan alone is responsible for getting your money back to you. If he doesn't get back to you, do everything that is legal to get your money back. The world does not operate on morality and trust: it operates on a strict, enforceable legal code.