I think Sazandora has a lot to offer over SpecsMence. If SpecsMence does run Modest, you'll squeeze 350 Special Attack out of its base 110 and 299 Speed out of its base 100 Speed with an EV split of 252/252. Sazandora gets 349 Special Attack (the single point doesn't matter) and 324 Speed (those extra 25 points matter one hell of a lot). Therefore even if Sazandora is under more pressure to run Timid, it's still getting matching or higher stats than SpecsMence in all the areas that matter besides HP (where the 3 base stat point difference is offset by the 10 base stat point difference in Defence/Special Defence). Arguably, SpecsMence is only better than Sazandora if it exploits its Speed advantage and runs Timid, which makes SpecsMence quite a bit weaker than Sazandora and only 4 points faster (though it's true that speed tying with other base 100s is pretty huge).
Also, I don't think it's fair to say that SpecsMence is less predictable than Sazandora. If we're being honest, SpecsMence has 5 viable moves for a Choice Specs set, those being Draco Meteor, Dragon Pulse, Fire Blast/Flamethrower, Hydro Pump and Hidden Power (which is a pretty rubbish option). Sazandora however can choose from those five options (with Surf instead of Hydro Pump) as well as Earth Power, Dark Pulse and even Focus Blast. With a more usable special movepool, I'd say Sazandora is the less predictable one; I guess one can assume both will always run Meteor/Dragon Pulse/Fire move/Filler-which-really-needs-to-hit-Heatran, but Salamence has only two choices for its filler whereas Sazandora has four that can hit Heatran (EP, Surf, HP, Focus Blast) as well as the Dark STAB.
On a slightly seperate note, what does everyone think of Focus Blast on Sazandora? On Specs it hits T-tar, Blissey and Heatran really hard and should OHKO Tyranitar, though accuracy is a big issue and Heatran dies to Surf/Earth Power anyway.
And on a completely different note, is there much point running max Speed on Sazandora? I guess it'll depend on how popular Ononokusu (147 Atk/97 Spd Dragon) is, but I reckon you could drop to 319 Speed to get the jump on Gliscor and chuck the remaining EVs into HP, which might help out when taking resisted hits.