I think the most important question about whether or not to run for SE is what the beneifts might be to you personally once you are there.
For the last few years I was doing a lot of trips to LHR, and without doubt being able to UG from H was such a huge difference that it was worth a run to SIN to get to SE last year.
I have used KK a couple of times, but dont have a large number of miles, so that is not a big deal. Makes life easier of course
I am SE for 2004 but am really thinking whether it is worth ensuring I make it for the followign year or not. My trips to LHR are much less frequent now, and given that E can UG from H everywhere else, the benefits are not that much greater for SE.
As others here have noted, I think you need to be doing a lot of international flying or have a lot of miles banked that you want to redeem to make it worth doing mileage runs to get SE. I would want to be sure I was going to be flying to Europe a lot the following year before doing 70K in runs.
I still think E is great value except for the KK.