Its all about personal taste, take for example Peter Froud's Coug - not most people's cup of tea, but its different and Peter loves it and thats what matters.
IMHO, its a close run thing on the best coug i have seen in the flesh so to speak, very close between Al's frosty , Dave's (dyg) green st200 and Lazybones' blurple.
I like both of mine, but they are not in the same league as Al's, Dave's and Tony's, although I don't think Tony would mind me giving most of the credit to its former owner Phil Robbo. I would glady swap one of mine for that one