The answer to your question is impossible to answer, when it boils down to it. I find DeepSea's lack of 'auto-incrementing' hights/depths/light-level of sectors a royal pain, and having to switch between Thing/Linedef/Sector/Vertex mode manually really sucks. I also use DeepSea, and am really trying to make it my fave, but so far it just can't beat Wadauthor for me. Copying from one level (even another game) to another is a simple matter of copy-paste. It has it's qurks, but what program doesn't? I can create a base level in Wadauthor in minutes. My personal 'best editor' has got to be Wadauthor. Of them all, DeepSea has the most 'features' it truly is an 'all in one' package. I'd put my money on DeepSea, Wadauthor, and maybe DOOMCAD (for purly DOOM editing). Simple: whichever one you are use to and does what you need.