It better fit the look I was going for anyway, but I also wanted it to cushion fan vibration. As is the window, despite being pretty thick, can still flex and vibrate as the fans generate backpressure and themselves vibrate somewhat, but the effect is reduced by the u-channel.I think U-channel makes everything look far more untidy tbh... there is always the join and it just looks a mess... Do it right, spend the time and you cant tell....