Is Destro Lock viable in PVE?

Hello,

I have been talking to a friend who has told me that Destro does not work at all in PVE and I would never get invite to RAIDs.
Is there any true there? Is Demo that superior?

I am quite new to Warlock and wanted some input on this matter, please.

Demo isn't superior to destro dps-wise. It's just the default spec every raid requires to run due to the raw amount of SP it provides.

If you want run a pure-dps spec as warlock most people will hit you with the stigma of "you're at best a bad mage". Depending on gear/encounter warlocks can be quite competitive though.

Damn, that is just sad.
I wanted to play it as Destro, but it kinda puts me down.

I think if you're just looking for the 'fun' factor, you can still play it as long as your raid group/guildies are okay with it?
But if you're pushing progression and prioritizing the overall raid benefit then you'd definitely need to be Demo - for the sake of everyone - at least until everyone's close to BiS and just want to chill

I'm a demo main and I've been playing around with a destro OS. Idk about the different stages of gearing, but at 6.1 gs the dps is on demo level, just more consistent since you don't have an execution phase or strong cooldowns like metamorphosis. It just kind of pew pews equally throughout the whole fight, chill af but also a liiiitle boring. It might pump a bit lower or higher based on the fight.
Sadly your imp's blood pact doesn't stack with other hp buffs so in a 25 man setting the only utility is a bit of mana replenishment from Improved Soul Leech and an AOE stun (shadowfury). Nothing here beats out demo's Demonic Pact in any raid comp, so it's only viable if you already have a demo in the raid, and even then affliction is generally preferred for its higher dps (it's close but there is a lot of stigma attached to slightly suboptimal specs).
Bottom line is it's perfectly fine but demo is strictly more useful and if there isn't one in the raid people WILL expect you to respec.