While it IS good, it is major-league outclassed by standard Latios. Standard Latios can do the same thing Mega Latios can do with similar success whilst not taking up the Mega slot. Honestly, you're much better off running standard Life Orb or Soul Dew Latios than Mega Latios.
Verdict: Not worth using.
Here's a Latios move set tho! :D
Latios @ Life Orb
EVs: 4 Def / 252 SpA / 252 Spe
-Hidden Power Fire