The best answer is to ask first: what are you trying to do with it?
I have two swords for two very seperate occassions:
A 15>50 longsword 10/10 sundering with +30 fortitude
AND
A 15>50 longsword with 3/1 vampiric and +5 defense
They have different purposes. I am a professional runner, running elite clients to the forge, through the ascension missions, to granite citadel, and so forth. When running I don't use my sword to fight and I don't get hit enough to do much damage, I don't want a constant health degeneration from my sword that can't be offset by attacks, and I am targeted by health degeration spells that ignore armor and chew through my health. Plus I do like to have something very expensive and flashy to inspire confidence in my customers. The sundering longsword of fortitude is perfect for runners.
When fighting, the vampiric longsword of defense is the way to go, as it deals plenty of damage, some of which ignores armor, and when fighting, extra armor is invaluable and comparable to 30 points of extra health. So when I am using my sword as a sword, the less expensive mods are the better ones.
Ensign's point is that most people need a sword for the latter reason, not the former, yet they still buy swords like my top one, which doesn't make a lot of sense.