It's a personal preference thing really, but I personally prefer square gates now, and this is from a former pad player.
I used to hate the square gate with a passion when I first switched from pad to stick. It made all those pesky DPs, 236, 214, and half circle motions a pain in the ass, so I switched to Octo gates. It definitely made stuff easier instantly at first. After awhile though, I naturally just stopped riding the gate, but then I started messing up in other areas. The advantage of the square is feeling the diagonals. On octo, SO many times I would be on 2 when I wanted to be on 3. Playing Mu 3C was important, so doing 2C on accident over and over was no bueno.
The solution, changing back to a square gate, so I KNOW I'm on 3 and not 2 since it's placement is pretty obvious on a square.