I've tried these both back in beta when I could drive tanks (I was actually specced for them), and hopping into the gunner seats in random people's tanks.

From my experience they are just an utter waste of space. In dumbfire mode they are insanely inaccurate because they can have a HUGE area around your crosshairs they might hit within. If you aim DIRECTLY at a vehicle they will lock on within a second or two. Of course since it requires a direct aim, you could be pumping rounds into them during that time with a blaster or charging up a railgun shot.

Of course you can trade your useless lock on ability for dumbfire missiles with a spread the size of Rhode Island as opposed to Alaska.

But I can't claim to be the best missile turret user. Has anyone found any tricks for using them effectively? Anyone (that uses them) willing to make the case for their defense?

Dont move while shooting, thats what really fucks up your aim since the missiles will 99 times out of 100 hit off target
Ambush tactics are key

How do you lock on with missiles?

Large Missiles aren't that bad, you just have to use the fragmented one for anti troop, and even at medium range you can usually hit 2 out of 4 in the volley at your target while moving. A Madrugar's worst fear is a Missile launcher, and as long as you can hit a few times, you are golden.
As for small turrets, only use them on the HAV small turrets, they only work best there, LAVs move too fast.
Missiles are great in the ADV level, but they only are good against Madrugars and installations. They are a blast to use against infantry, but sadly you can get rail snipped. :(

1) Don't need the fragmented for killing grunts bc only a direct hit will kill them, anyway, and using a fragmented will make you die to other tanks faster bc it reduces direct damage in exchange for 1m extra blast. Not worth it.

2) No. A madrugar's worst fear is hacked exo-av nades

3) You got the small turrets right. CCP need to fix that...

4) No. You can kill infantry well with them, but yeah, a well fit gunlogi can tank explosive damage all day.

I'd recommend you give up on missiles and switch to rails. Seriously, though: talk to Earl James or General Grodd bc theyre godly with missiles.

I don't know how people make large missile turrets work, but they do, because people can absolutely WRECK my armor tank with that equipped to their gunnlogis.

With small missile turrets, get up to the advanced level and buy AT-1 cycled missile turrets, and put 'em on both of your small turret slots.

Since missiles are so incredibly bad with aiming, you'd think that they'd be totally useless, but that's not the case if you can get one or two buddies into your tank who just sit there and spam 'em in the general direction of the enemies. It makes a terrifying wall of missiles. It scares the people the **** off, or if it doesn't scare people the **** off, it'll actually kill them, because it's a wall of ******* missiles and at least one or two are going to hit you eventually.

Only advanced? Piker