To everyone saying that the SE is going to be your last iPhone that you buy... what are your alternatives? None. Because no one makes phones that small, and those that do, won't in a year or two because the demand isn't there sadly.
6 months ago, I sold my SE and bought an X - and although the SE was a great phone for a long time, the X isn't really that much bigger to use but gives you so much more screen and is much more functional for anything other than texting, email and the rare web search. The majority of users, not all, but the majority use their phones for much more than that these days. It's their camera, their games console, their on the go cinema etc.
Hopefully in years to come, when technology and the cost of the bezel-less screens comes right down in comparison, then Apple may well bring one out. But ultimately, if the SE was making money, they'd have kept it. They've been cheap for a long time now, almost given away by some companies (free phone and £10 a month contract for example).
Seeing the new range of phones, I'll be staying with my X. It does all I need, is a great phone spec wise, and has been faultless since purchasing it, has been cased from new and still looks like new. Plus, no one is going to know it's not the latest anyway as there's no distinguishing differences really.