Which one is better just depends on what you are fighting. Fighters are good against other strikecraft and most lightly armored ships like long range frigates, siege frigates etc. Bombers are good against ships with heavy armor like Capital ships, heavy cruisers and structures/starbases. I usually have more fighters than bombers because there tends to be more LRMs than heavy cruisers, and because air superiority is usually far more important than the extra damage bombers do to capital ships. That said, I usually have a couple of carrier cruisers in reserve loaded with nothing but bombers to be used against starbases, though they've often proved useful for supporting my main fleet as well.

To be honest I dont think either or is better or worse, I think they need each other. Bombers need fighters to cut through the enemy flak and fighters so they can do their job. And Fighters need Bombers to deal heavy damage that they cant provide.

I always go 60% Bomber 40% Fighter. That way theres a balance. Plenty of fighters to defend bombers. And plenty of bombers to completely devastate an enemy.

Vasari bombers are tough as nails and can bypass shields with phase missiles. If you're Vasari, you'll definitely want to invest more in these than their relatively weak fighters (unless of course you're facing opposing bombers). Be sure to keep some sentinels around to  kill enemy fighters and keep your bombers healthy. Another nice thing is that sentinel weaponry takes the same upgrades as bombers, so upgrading your bomber firepower also upgrades the firepower of your sentinels, and you can upgrade sentinels to do splash damage to enemy strikecraft. They are excellent at killing enemy fighters. If you're good with micromanagement, Vasari bombers are the way to go.

Advent bomber spam is the worst.

i always go for a full fightr spam

for the simple reason that my fleet is here for taking care of ships ^^ the fightrs are here to take air control

only reason i would make bombrs would be to take a sb without confronting it

an other reason to use fighters is that they use a lot less am to build then bombrs ^^

when you have a mobile fleets and loose air from battles its the only reasonable choice

Wow really ?

Fighter spam all the way ?

As for specific situations, if fighting Advent I always go for fighters, as the main Advent strategy tends to use Illuminators/bombers or scouts (all strong Advent units) and fighters can deal effectively with them all.  For everything else, there's HC.

If I'm using fighters myself my fleet will probably be comprised of less fighter vunerable units (like HC)  and/or Hoshikos to the point at which the fighters' ability to effectively damage my units is moot.  If both of us are using fighter heavy strategies, well, time to switch tactics to lf

I think your babying your Fighters and Bombers if your scared to launch them due to a counter. Really your only limiting yourself in that manner. Unless they have spammed an entire fleet of flak. I dont see why you would hold off on launching them.

Theyll seriously be fine. And like the manual states. Their a staple in the Fleets arsenal. If you allow your opponent to scare you into grounding your SC in fear of losing them to flak. Your opponent already has to upperhand.

Actually I general have about a 50/50 in my fleet

^ Im not saying dont keep your SC docked at certian points. Because I personally launch my Fighters about 30 -45 seconds before launching my bombers to give the Fighters a head start on slamming my enemies Fighters. My point is, Dont bring SC to a fight and not use them at all. Its a waste of effort to build all of that and then to not use it intentionally. Yes flak will beat up on SC but at the same time. If your SC numbers are high enough. You wont notice the insignificant loses. The one thing I do technically spam is SC because they are the true backbreaker in a battle. They can quickly swarm a Cap before its healers can warm up and they can percision bomb and destroy absolutely everything while your fleet stays out of direct harms way. Id rather throw my SC into the wind knowing they can be rebuilt during battle then my actual Fleet that has to wait for reinforcements multiple jumps away when it takes heavy loses.

I dont baby something I know to be even stronger then it is fragile.

Yeah, doing that is SO funny, I mean, you could have a fighter squadron just go around and around the GW at the start of a battle, get id of their flak frigs from the main fleet, or force them to micro-manage every combat moment, which is HARD in MP.