I've got a similar one made by Hach and it is definitely way cool. Send me you e-mail addresses and next time I use it I'll e-mail you a reading. Actually, the electrode seems pretty good for general purpose use but I haven't tried it in wort (beer, yes).
Since you have gotten me thinking about the double junction thing another point came to mind. Test solutions are, generally, less than saturated with KCl as the fill solution is. Thus water will try to move through the junction diluting the fill solution (and changing the diffusion potential picture for the reference). This is the main reason that one should not store an electrode in DI water but rather in a solution of KCl of the same strength as the fill. A double junction gives additional protection against dilution from water incursion during measurements but obviously if the electrolyte flows out of the body (as it should) faster than water migrates in you are OK. I think the flow mechanisms in these newer electrodes must have also been improved.
Another thought is that we may get away without junction clogging because of relatively infrequent use. In daily use in a commercial operation...? Those concerned with junction fouling, from whatever cause, should buy electrodes with renewable junctions rather than double junctions. This option will cost you.
