I'll leave my Sorc opinion here (Pulled it from the past threads where people asked about Sorc sub):
Yess, it is. I, king of the GunSorcs, shall lead you onto the path of righteousness!
What is a GunSorc?
A GunSorc is a DPS-Support class. Combining the high-DPS output of the 'Slinger with the double-debuffs of the Sorc, you can handle a wide variety of situations and get a target down faster than any other ranged class, with a better rate of survival!
Why don't I just go Sorc/Gun?
The cooldown rates of the subclass skills is roughly three times their original cooldown. You will not be spamming your Sorc skills (Minus the one stackable DoT), as you only want them for their DoT effects. Your Gunslinger skills are the ones you should spam as they have higher damage, shorter cooldowns, and you can actually move while casting them. Ontop of this, you will not receive the shield buff from your traps as that only works if your Main class is Gunslinger.
How are they in PvE?
You'll have no problems dealing with Normal/Elite monsters, and the same goes for Bosses if you use strategy. Simply staying at a mid-range distance and spamming Aimed Shot, Bombardment, and Sonic Boom after using Demon Seal and/or Blood Seal is the usual routine. After the boss uses its red-area AOE skill, quickly run into it and place both traps (Frost, then Dark) underneath it immediately, then distance yourself again and resume shooting. This will drop the boss faster, especially in parties. The skill Decoy will allow you to hypnotize an enemy Normal/Elite monster and have it attack nearby enemies, while taunting them so they're forced to attack it until the hypnotism wears off or until the target dies; a very good emergency skill. Sleep Totem is very good for crowd control as there is no limit to how many targets it puts to sleep, and Rejuvenation Mantra is your average HoT that doubles as a debuff remover for you and your party-- a great tactic when used with Blood Seal while kiting a boss monster. Overall, you have more versatility than any other subclass would give!
How are they in PvP? You will wreck all melee classes, very often. The only exceptions to this are:
1) They greatly outgear you.
2) You have little to no Accuracy stat'd on your gears while they have high Evasion.
3) They get into close-range of you and immobilize/stun you (This one doesn't happen often with good Move Speed and keeping Aimed Shot on them, but Ravagers will accomplish this the most).
Against ranged classes, it's a hit or miss. You get the sleep totem on them and then follow up with the two traps,and they're dead. They do the same, or stun you and follow up with crit hits, and you're dead. The main downside here is that a Ranged class isn't going to just walk into your trap (Not in a 1v1 anyway), and it's going to be hard to get close to them to Sleep Totem, especially if they have a stun ready. In this case, it's best to just cast a frost trap underneath you for the Shield buff and then do as much DPS as possible without trying to chase after them.
How should I build my gear and place my stats?
I don't believe in a perfect build, so you should feel free to use what you see fit. But for my build, I run DMG/CRIT/HP gears with all my Offensive points to SPD and my defensive to HP. GunSorc is a very fun class once you get the hang of it, and it always feel good to be more than just a 'DPS' in parties. If it interests you, don't hesitate to give it a go!