1 minute, 5 minutes, whatever. At Guy's speed, he can land many gated attacks. The chakra that envelops him when he's using gates is increasing his power drastically, so he's basically going to pierce through it with brute force. If not, he'll push the sand back and the sphere will be broken. And he could stop those swords because he was focusing his chakra towards his defense, plus that Guy's attacks are multiple and fast. No time for Gaara to react. And I already told you that he doesn't need gates to dodge Gaara's attacks. And watch the Lee vs Gaara fight. Lee is like Gaara, and we all remember the speed Lee got after taking off those weights, and he wasn't using gates there. Indeed, that speed to attack might not be enough, but it is for dodging.
Gaara only was able to fight 2 days because he stopped two times. Once it was night and nobody was fighting, and once he was knocked out and was treated by Orochimaru. Guy's attack is certainly not a 1-powerful-shot as that arrow, but it's a multiple attack with multiple gated chakra punches in a matter of milliseconds. Gaara doesn't have the speed and power to keep up with that.
