I've played the 5 levels on normal and tried the first one on violent. Very fun and intense. Nice old school asthetics and good music (especially for the last boss, it was quite intimidating). The movement is nice and fluid thanks to the dashes and slams. Enemies coreograph their moves clearly, giving just enough time to react and so deaths don't feel unfair. Health is rewarded by killing enemies up close, a fun risk and reward system (kind of like Doom 2016).
The two guns (pistol and shotgun, not sure if there are others hidden as secrets) feel nice and powerful. At first I felt the pistol would be redundant once I got the shotgun (due to unlimited ammo), but due to the shotguns slow reload I found that I often switched between the two depending on the situation. I really like how the health and stamina is displayed clearly about the crosshair, so even in the very intense moments I can easily see their values.
I like how the tutorial drops you straight into the action, adding instructions after each room so you can try the technique out without being overloaded with the new mechanics too quickly. The levels build up in intensity and variety nicely too. I couldn't find the secrets although I didn't really spend time on that, might try that in the future.
One negative would be that the framerate can drop when multiple enemies are killed at once in explosions or when dropped through the floor, which hopelly will be improved in the future (I played on my laptop which has an i7 8th gen CPU, GTX 1060 6B GPU and 16GB of RAM if that helps as a reference).
Another thing possibly would be that the final boss fight in the Cerebus level is significantly more difficult than everything that proceeded it (this was on normal, haven't tried on violent yet). Don't get me wrong, I did enjoy the fight for its difficulty and since the boss indicated its different types of attacks clearly I didn't feel cheated when I died. I do like when a boss is difficult and requires multiple attempts to kill, as this makes the fight memorable and satisfying when they get destroyed. I just felt the jump in difficulty was a bit too sudden, perhaps making the end of the previous level a bit more difficult to ease this difficulty spike. I could be wrong though and maybe others disagree.
Overall I really enjoyed this game, and look forward to its future development to the final release.
(This is the first time I've ever given feedback/review for a game I've played, so I hope its helpful)