Prosper.com Senior DW Developer interview questions

I applied through Linkedin and their website as well. A recruiter/HR got in touch with me and after the the first phone screening, I was scheduled for the onsite 6 interviews lasting 3.5 hours. Interview details were shared, but one of the interviewer got swapped with someone else. All the interviews were very simple. I was asked if I was ready to work extra hours or not. What bothered me is the fact that they were satisfied with my achievement, capabilities and experience and they did offer me the position of 'DW developer', not the 'Senior' position. When inquired about it, I got a response that Prosper posts 'Senior' roles to attract good resumes from the market, which in my opinion means that Prosper lies about the position. After I received the initial offer from them, I asked for some time to review it. They were very aggressive about it. After declining the position for obvious reasons, Prosper didn't even respond to my email.