I know I'm going to sound like a broken record here, but it really depends on what your trying to do with your char (pvp/pve) and your current gears.
For me on pve I try for 2k def on gears alone and that way you should'nt need any into CON unless you plan to pvp alot. As adek1994 pointed out, lvl your shields and then you can pump more into ESS and stay comfortable in most situations. If you find yourself needing max CON for pvp at GL lvl then either your gear or shields are lacking I would think. I've no experience in real pvp on D9 though so I may be way off here lol.
If you're into serious pvp then masha123 said it best

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Quote:
Originally Posted by masha123
STR 14
ESS with lvl Berce
WIS 300
CON Max
DEX 14
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