Version one has possibilities — especially if combined with version two. It’s similar to the existing logo, which could be good as far as maintaining brand recognition or bad if the client wants something totally new. You definitely need to increase the widths of those thin lines between the letters, however. They will totally fill in when reproduced at small sizes.
Version two has possibilities too. The arrows certainly imply movement (or transport) from one place to the next. Why, though, did you cut off the end of the crossbar on the T?
Version 3 is nice, and it looks Irish. I don’t understand to purpose of the point protruding from just beyond the top of the f, though.
I like version 4, but it’s too reminiscent of the drain pipes beneath my kitchen sink.
If it were me, I’d combine the best features of version 1 and 2.