Both headphones are fantastic it really just comes down to personal preference. I had the Steelseries 9h closed back headphones for a while before I switched to the Sennheiser HD598's and I prefer the open ear much more than closed as it keeps my ears a little cooler and I like the way it sounds a little better. Sort of an unfair battle though as the HD598's are clearly tiers higher than the 9h over all but my point stands. The only downside to open back is if someone is vacuuming in the house or mowing the lawn outside I can hear them but it's not like it ruins the game or anything. I highly doubt theres a giant advantage or disadvantage between the 2. Some argue open back makes the sound stage larger therefore it's easier to pin point sounds aka enemy footsteps. Do some research on open and closed back headphones for more info. I might suggest buying one pair through Amazon as they have a nice return policy. Order the open back ones first and if you find you don't like them after a few days return it and order the other pair. You'll lose a couple bucks on shipping but it's worth it if you get the pair you like the best in the end. Either way you won't be losing games because of the differences between the two. Best of luck!