I have one report that a remnant PW3-4G sold here in Germany in a minor brick-and-mortar-store with an out-of-the-box fw 5.8.6 (or so - anyway it was below 5.8.8) could be very, very smoothly jailbroken using the 5.8.9.0.1 factory build. The first restart after the "downgrade" to the factory version took only about 10 minutes, i.e. much less time compared to the 5.7.4 method, where it could - really! - take up to a full hour for newer devices, so impatient people could think that the downgrade failed and therefore begin to panic...
I suggest to use the 5.8.9.0.1 factory firmware whenever possible!
