I managed to see out my time contracting by ensuring back to back agency and client contracts outside IR35, by ensuring the service company retained the key rights - direction and control, substitution and so on. Essentially you just had to tick off all the indicators on the Revenue's list, but other real demonstrations of being a business in your own account helped too. Most agencies were willing, though I know when the revised agency regs came in they tried to resist. Yes, it meant you were doing more than merely being an agency worker hiding behind a PSC -- which for me turned out to be a good thing as it brought additional income and opportunities.
I never had an IR35 caught contract, though several started as clearly IR35 caught offers. I never walked from an offer due to failing to get it put outside, and contracts adjusted. The PCG - Professional Contractors Group (now IPSE) were a big help in combating the FUD, and suggesting successful counter measures.
If I ever went back to contracting, I sure as heck wouldn't be doing it via IR35-caught contracts. :)