I just ordered a Bernina 430! I am not getting a steal on it or anything ($1999), but I am buying it locally which is important to me. I should get it next Monday- yay! I am excited about it as this is a HUGE upgrade for me. I have never had a Bernina before but I liked a lot of stuff about it. If you get the 430, you can add the BSR later which is the only difference between the machines, I think.
I ordered one sewing machine in the past from e-bay. I had borrowed a friend's Kenmore machine and broke it. Rather than pay to have it fixed, I ordered one exactly like it from e-bay. I paid about $130 or so for it, because it was listed as "Like NEW!" and when I got it, it was really dirty and even smelled funky- they must have had pets. Also, the person who packed it used little foam pellets and they got all over inside the machine. One other issue- the thread holder pin was broken, which I believe was done during shipping.
So much for saving the repair cost- I had two broken machines at this point, but the one from ebay had not been used much so it was worth putting the money into it.
I brought both machines to a repair shop and the guy put the thread holder from the old one on the new one and cleaned it up for me. He said the machine itself was in great shape, so the seller did not lie about that. Overall it was an ok experience for me, but I would hesitate to do it again, especially for a high dollar machine that you will use for 20+ years. The only reason I did buy from e-bay in the first situation was because I wanted to replace the exact machine and they are not sold anymore. I probably spent more replacing this machine than it was ever worth brand new, but it avoided any hard feelings so it was worth it.
For my new machine, I am a firm believer in buy it where you will get it serviced. You are building a relationship with your serviceman because you are going to see him at least once a year for a looong time. They are going to treat you better if you buy from them.