Another thought for your consideration. I you take a regular length DT line one or two line sizes above your rod (1 for a 'traditional blank action,' 2 for a 'Euro action)'put a loop on the end of this and you've got a very good ... and cheap head system.

The long belly tapered lines such as the SA XLT'S and (especially) the RIO GrandSpey lines also work very well with the Airflo and Rio sinking leaders.

Probably repeating myself here, but with a dry line and a sinking leader combo you have line control like non-other.

Put a "butt section" of 3-4 feet off the tip of the dry line (I use 20# maxima MAIN LINE for line wts 8 and down, and 25# 8-9 Euro's or 9wt and above regardless. Tie a loop to the end of this and loop to loop to the sinking leader. Couple of feet of tippet material off the end of this to the fly(s) and you really are good to go.

System sounds like a "lash-up" but I assure you it works very well. The key to the thing is the 3-4 foot 'butt section' dropper. This allows the sinking leader to 'sink' and all of the dry line to float. With a 15'spey rod you can still mend the 'dry line' out to 60-70 feet.
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