I like to finger-shoot my compound as well as use a release, so a rope on the release is better for me than a D-loop. But if you use a release all the time, a D-loop is the way to go. It's quicker to use and makes for greater consistency.
I wonder whether you need to set your BT release more coarse? Most problems with BT releases seem to stem from having them set too fine.
BTW, Marcus made an interesting post on AF recently about D-loop length:
http://www.archery-forum.com/viewtopic.php?t=93224
Also check out this thread on BT release activation:
http://www.archery-forum.com/viewtopic.php?t=93214