Basics: Sorc. Mental Toughness, 1% Crit chance. Worth??

[nachodemon]

Most of the posts I read ignored the Mental Toughness feat for sorc. since the bonus SP didn't value that much. But I'm tempted by the 1% / 2% crit. chance for the burst damage.
It's true that items gives plenty of crit chance.
If not Mental Toughness, I suppose Heighten Spell would mean more DPS. But then again, my SP cost goes up with the other Metafeat.
Help me out:
Basic Feats : Empower, Maximize, Spell Focus, Greater Spell Focus.

Spell Pen , Greater Spell Pen
or
Heighten Spell
or
Mental Toughness , Improved Mental Toughness.

Thanks

[Singular]

On a sorc, heighten is great on your sla's - it's free (no mana cost) and increases the damage quite a bit b/c mobs fail to save.

Mental toughness, even though it's only 1%, is good if you want to min/max. It will increase your dps output and it's additive to improved mental toughness and epic mental toughness. All together that's an extra 3% (and spell points, which are always helpful). At end game, with past lives, and Thunderforged weapons, you can reach 48% spell critical if you take all of that. Even more now that there's a +5% insightful spell crit item or if you use a staff - so the more you have, the better you'll be in EE content, even if it's just a slight increase.