1v1, gear roughly the same.
In my experience:
OP/SC - We are dead. No questions asked, if you get into a 1v1 with a op/sc there is very little you can do unless you are playing against a under geared or bad OP/SC
Marauder/Sent - We are dead. Sure you can dot them and try to kite them for like an hour but good ones will stick to you like glue.
Juggs/Guardians - See marauder, only difference is depending on spec. They either kill you in record speed or shrug off dots like no ones business.
BH/Trooper:PT/Merc - Mercs can kill you really fast if you can't LOS them. Luckily most mercs don't know *** to do if you interrupt tracer missile and stand there like morons. But if you have played against one with skill its a different story. PTs are like marauders/juggs, but they bring you to them instead of the other way around
Assassin/Shadow - Probably our best match up (aside from other sorcs/sages), but not by much. If they get the jump on you the will win most of the time.
So in other words, yes. Sorcs are HORRIBLE 1v1. We have to rely on positioning and teammates in order to succeed. Don't get me wrong I have won plenty of 1v1s but they were mainly against horrible players, other sage/sorcs or people with horrible gear. Most of the time, I am dead if someone gets on me and wont get off. I make it as annoying as possible and even try to kill them if I can but the best case scenario is I run away and they quit chasing me.
Where Sorcs SHINE: Being left the **** alone. I can dish some crazy damage... Not soo much directly to 1 person but to groups. That is what people see on the scoreboard at the end of the game and why people think we are OP is because of our AoE. If you let a Sorc sit there and destroy you they will.
But to think we are OP is beyond stupid, the only reason there are a lot of us is because we shoot FRIGGIN LIGHTENING OUT OF OUR FINGERS, no really, that is the only reason. I would consider us middle of the pack. Dangerous when left alone but dead when focused.