I own the sE Z5600A, Z3300A, TITAN and SE3 (and foolishly sold my Z2200A).
The sE mics are made in Shanghai in the sE (Heavenly Sound) factory now, not by the Feilo factory. Havent been for quite awhile in fact.
Like Warren, I really like my Z5600A and as shared by Dave, a lot folks do switch out the Z5600A stock 12AT7/ECC81 for the 6072A/12AY7.
The Z5600A has been updated for 2007 (Z5600A MKII ) with quieter electronics in the mic as well as in the power supply plus it gets a 10 dB PAD and Hi-Pass Filter, neither of which it had before.
Keep your eyes peeled for whatever Warren writes about his A/B of these 2 mics as he is one knowledgable cowboy.
(xist, take few minutes and go here:
http://www.seelectronics.com/whatsnew.html )
Here is part of a review from MIX : "Bottom line: At $229, the Apex 460 is a phenomenal buy and although it will never replace its higher-end brothers, it stands up in its own right and does a decent job in a number of applications.
Besides, at this price, it's one that you wouldn't mind opening up to dink around with the electronics or to change the tube. I've already seen modded units available online with a lower output and quieter tube, along with some capacitor changes. This is not a mic aimed at the high-end user, but at the hobbyist and/or home studio owner. For that large chunk of the recording public, owning this mic is a no-brainer."
I know Dave Thomas does some magically awesome 460 mods but I personally can't see how the APEX 460 would be even close to the Z5600A MKII right out of the box.
However, I'm just a homestudioguy