I’m French and I apologize in advance with my English. I play on PC and I’m a average guy on FPS except this Halo for some reason(im garbage).
After a lot of sleepless nights, monster energy and tryhard against bots that lasered you at the end of the map with the pistol : What 343i presented us is very promising!
It’s not a “Halo 3.5” nor a “Halo of duty : Advanced Warfare”(do you feel my salt) but a new Halo.
The gameplay is good, lively and fluid with a good sandbox and 3 maps that are well designed for a Halo. The sprinting problem is over since it is like ~5-10% faster than the race so you are pretty fast from the start.
The AI in “marine” difficulty is not hard but you have to be careful but in ODST please it’s aimbots that kill you in “perfect”. Spartan difficulty will be a Vietnam War with no chance to win.
Customization is Reach pushed to the max even if I’m not a big fan of “Armor coating”. I think everyone can be unique (until everyone gets the samurai armor).
Weapons:
The assault rifle which is viable, kills quickly if you learn to shoot in bursts
The mk50 which is the gunfigther Magnum: Good rescue weapon and fast to deploy: It is not H5 or CE Magnum
The pulse rifle : I can’t play it lol
Commando is powerfull when im not braindead
The BR is BR
The Ravager is a monster in impact but its loading shot leaves something to be desired.
The shotgun is buggy, weak, and lack of ammo
Heatwave : powerfull , wierd and lack of ammo
The impaler which is a truck launcher 
The problems I encountered: I feel like I’m shooting ghost bullets while I have his head in my viewfinder and bloom is reduced, FPS problem, crash, collision and especially the bulldog is -Yoink- the projectiles do not go where I aim and I do not think the flash grenade exists in Halo and The PC version is weird overall, can’t put the word.
Conclusion : Good Tech preview, the bulldog is crap and Hon hon vive la baguette.