I must say there still is not a *huge* difference between E and SE. Waiting times on the phone are less of an issue. SE services, aside from concierge (which is accessable to all international J pax) are not too different anymore from E. There is no EP-style check-in area, yadayadayada...
But the upgrades are definately a BIG benefit for SEs.

Don't get me wrong, IMO it is a great tier, but SE could do with some improvement when compared to incentives on offer with top-tier of other carriers. Other carriers have massive mileage bonuses, etc. Eg BA has a 100% mileage bonus on all flights for their Gold card holders. I think 100% is a bit nuts, but right now SE get nil.