I appreciate your request but I don't have to be the only one to answer gun related stuff. Let's take a look at one of the commonly compared EC guns.
Luger
+ 10 damage (upgraded)
! Comes with a nice briefcase
+ Fastest reload speed in the game
+ 15 clip size
- Average rate of fire (slower than ak47u)
- 40 ec (more expensive than ak47u)
+/- Fired from the middle of the character (It does not greatly excel in either area in spar but adaptable in general)
Ak47u
+ Fast fire rate
+ 35 ec
! Comes with a flashlight
- 9 damage (upgraded)
- 14 clip size
- slightly slower reload speed
+/- Fired from the left side (Balanced against left handed enemies. Advantageous or disadvantageous against right handed enemies based on location)
Luger is one of the light weight 10 damage guns. For a 10 damage gun, it is on the lower side in terms of freeze rate length. The lowest freeze rate 10 damage gun being the Neo rifle. What you should not expect with the Luger is it's kill speed. It's rate of fire isn't as fast as most other guns in it's tier range. Even if the Luger is a 10 damage gun, it's rate of fire won't be enough to outdamage the more devastating weapons. The luger strikes a balance between pking and sparring. Despite being not that powerful in kill speed, it's actually useful in some pking and basing situations. The Luger has one of the fastest reload speeds in the game. That means you won't have to worry about reloading by accident and having your character freeze in a position that would make him/her vulnerable. If you are good at aiming, you can be firing with the Luger, seemingly endless, despite it's lower end of the rate of fire. Even though the Luger doesn't have very fast fire rate, it's faster than most other 10 damage guns in the game until around 100k+. The Luger is a bit more of agility with well aimed shots that makes it powerful. If you like to rush in and get as much burst damage as you can, Luger might not work out for you.
Ak47u is easier to use than the Luger but also deals less damage than the Luger. Hit and run tactics won't be as effective with the Ak47u. This weapon works great in sparring and performs fairly decent in pking and sparring. Sparring is where this weapon is often found to be used in. Having great capabilities of cornering in enemies. However, it's one of the more general weapons, as it does not have the most notable selling points (other than its flashlight). It's a left handed gun, standard 9 damage when upgraded with average clip size and reload time. You are also less maneuverable while firing bullets. Position yourself accordingly before spamming.
It's worth noting that both weapons still excel greatly in both sparring and basing. They are both capable of cornering in enemies. Luger requires a bit more aiming and timing but also is more rewarding with each shot landed. Ak47u is easier to use, but you may need to be in the enemy's line of sight a bit longer if you want to deal more damage.
Get the Luger if:
-You prefer less spam and more damage
-You can can control the rate of fire with proper tapping rhythm (It's semi auto)
-You tend to move around a lot before firing again
-You do not have the Sawed Ak and you need a balanced 10 damage gun (Sniper rifles - excluding L96a1 and neo rifle - have heavier freeze rate)
Get the Ak47u if
-You're relatively new to sparring
-You have a hard time hitting enemies
-You tend to lose out often in a bottom spar duel
-You like higher rate of fire over damage
Personally, I find Luger more rewarding when mastered. But it's not a major difference over the Ak47u. Find your playstyle and select the right gun.
