Taking a close look at the other Marks, I would say Mark of Nessus is sexy (basically, due to the wording, if the caster or special ability user fails their save against the ability, they can't use a spell, spell-like ability, or a supernatural ability that affects you. At all. And they make this save EACH TIME THEY CAST SOMETHING AT YOU, until they succeed. You know, there's a build in that somewhere...).
Mark of Avernus has its uses, I would say; Immediate actions can interrupt other actions, iirc, so you can basically 1/encounter prevent some idiot from doing pretty much anything. Also, it becomes borken with Synchronicity+Martial Maneuvers; basically, you just got a free +4 boost to attack and damage, as well as auto-confirm crits.
Mark of Minauros is hilarious with a Roof-Jumper build; your drop from orbit gives you +1d6 damage and +2 to hit for each 10' you travel! I think this can get us a record, non-infinite attack roll... Considering that, iirc, there are some abilities that trigger when you beat someone's AC by a given amount, this is sexy.
Mark of Malbolge is great for out of combat healing (even with a 10 in Con, you are getting on average 21+3*(HD) hit points back.) Also, it gives a nice 1 round boost to speed or reach... Get a Constitution of at least 24, and you have unlimited uses, unless you are using Ruby Knight Windicator cheese.
And... those are pretty much the only good ones.