If I was limited to one length for all my fishing, 12 months out of the year, short casts to long casts, wind, no wind, tight quarters, open bars etc. etc., the length of line would be a shorter head (Windcutter or SA Short Head). The reason I didn't go with an even shorter head ala Skagit/Scand. is because come late summer/fall, there are some reasons I fish where it really is necassary to cast a fair distance and I think the Winducutter/Short Head allows me to achieve the distance a little more consistently with a little less stripping.
On a side note, there was a period of time where short heads, and Windcutters in particular, recieved a bad rap because many people labeled them as a 'bad habit creator' for beginers. Over time, I have found that label to be a little harsh and believe that it takes plenty of skill to cast a Windcutter/Short Head/etc. 90' when you consider all that is involved such as rod stop, managing coils of running line etc. If someone who has never picked up a longer belly line can effectively cast a shorter head far enough, with an adjustment in timing and lift and such, that caster will have the skills to cast a longer belly or long belly line just as far as well.