[guineapig]

I would say it highly depends on where your int/manapool is at not including the robe slot and also on your current level.

The reason being is that, while hitpoints are usually more important than mana for a necro, at lower levels the 9 stamina will not give you a very big return. Also the 20 mana is guaranteed but the +5 int means different things at different levels/int soft caps.

The +dex is pretty cool however at lower levels when necros can still melee the mobs they are fighting (ice crystal staff). Also the +15 poison will give you a better return than the +5 magic in most situations unless you are on a raid (non-trak raid) where stacking SvM is key.

Personally I would carry both robes so I can swap depending on the situation. Both have good attributes.