That would depend on a few things, first of all are you going to use the table without a table cloth?
Do both styles match the room you are placing them in? (such as your chair)
If you answered yes to the above question I would take the more expensive one (the curved one)
The shape is much more friendly towards the purpose of gaming and general purpose pc usage. Since you can move around and let's say one day you are not gaming on both monitors but working/ browsing on 1 and then playing on the other and you pause your game now you just swivel your chair and bam you are in a comfortable position to browse, hell even watch a movie. Where as with the rectangular shape you are very limited
It's also allot more comfortable on your elbows if you can position yourself withing the curve.
I work at a curve desk everyday of my life and it's very comfortable...
Just remember to position the monitors a bit back so they are not in your face.