I've had my Hennessy Hammock for about a year now and love it, but I do miss the openness of the DD Frontline when used with the bug net underneath it.
After looking on Hammock Forums I saw that people were getting there Hennesssy's moded by having a zip put in, all the way round the bug net. Posting my hammock to the USA was going to be to expensive so I kept looking and found UK Hammocks which did the mod and were UK based.
After contacting Mat from UK Hammocks I sent him my hammock and a week later I now have a Hennessy with both the underneath opening and a full zip. Very happy with this but have yet to get out and try it yet.