I pre ordered Space marine back in June and I got early access to the demo.
First off Keep in mind that I am trying to be non biased in this review.
Even though I am a servant to the WAaargh.
The demo allows you to use six weapons.
The Bolter pistol A sniper rifle Bolter some sort of remote grenade launcher and the obligatory chain sword. There's also a power axe on the first level. You can hold four ranged weapons plus a melee, if you want to use the melee all you do is push RMB left is shoot.
The weapons feel good it does take a few bolts to level an ork but I'm ok with that orks are tough plus it's not going to be fun to have 30 round = 30 dead. When you kill in melee blood splatters your armor. The melee weapons are awesome and essential you are not going to be a level with ranged only orks are always going to be charging at you so I found myself emptying my bolter then mopping up with my chainsword, tank bustas and flash gitz are in the game I think and they stay at range Their weapons are dangerous keep than in mind your bolter is going to be needed.
I also got to use a jump pack which was awesome. It felt like I was an assault marine.
That's about all I have to say but relic did a good job with this game considering their usual genre. Hardcore boyz will notice a few things like it's closer to DOW than but in terms of gameplay it works out.