We use a lot of variations with our athletes, both for leaving no weak spots but also due to injuries and joint problems caused by sports. So many of our athletes have developed shoulder/elbow issues from their main sports that the weight room needs to be a place to rebuild safely without neglecting any area of the body.
For Dumbbell bench, if you are suffering from any shoulder issue, I would suggest using the Neutral Position Dumbbell Bench. So much of the shoulders (especially the joints) is taken out of this movement which will allow you to continue to build the chest and tri's while protecting the shoulders.
For those without injuries, I would encourage you to do both styles, but the standard DB bench is great for hitting the full chest while activating the shoulders and triceps. I'm not a fan of neglecting variations and this movement can be really overdone by younger athletes who bench way too often so I would encourage you to utilize the neutral position more but if you are looking for more strength, you will find it with the standard form.
Now for the best of both worlds and for protecting the elbow, rotation is gonna do a lot of you. I prefer to start Neutral and rotate the dumbbells as you go up (think of this as the Arnold Press of Bench). This movement just feels so much more natural for me and the benefits you'll get when it comes to elbow protection is amazing.
Easy way to decide what to use:
Shoulder issues: Neutral
Elbow issues: Rotate
No Issues: ALL THREE!