I have one of the new Airflo Long Deltas, you are right, there is is no splice. While I briefly cast the Delta yesterday I can speak more about the Long Delta as I have had it for a couple of months.
While I am not a devotee of shorter speylines, I am not against them either. I see a niche for this "mid-spey type" line in my fishing - especially on some of those nasty Thompson afternoons when the the wind quarters upstrean at you. The Airflo is amazingly slick and it seems to me has a very slim profile - really cuts the wind, yet unlike the other line that incorporates this characteristic in its name - I find it pleasant to cast.
You can get additional life by splicing the running line to the head (See Dana's article on custom lines on the Spey Pages)or you can put a blind spliced braided loop on the head and running line and treat it like a shooting head. It should work fine and give additional service.
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