There doesn't seem to be much love for the Buffalo bar around here? After struggling for about a year or so at home trying a straight bar, getting pain and going back to the safety squat bar several times, I had the opportunity to try out a Buffalo bar last weekend at Brussels Barbell (thanks, Steve!).
It allows for normal low bar back squat mechanics according to the book. The only difference is that the curve of the bar allows a grip that puts less pressure on your arms and elbows, which helps if stiffness prevents you from getting a safe grip.
What I like most is that the grip and squat mechanics are similar to a straight bar, which means you can squat just as heavy as a normal bar. It should hopefully also make it easier to graduate to a straight bar eventually. I intend to get one for my home gym, make my grip smaller over time and then switch back to a straight bar. And if that doesn't pan out, I'm fine just settling on the buffalo bar, with the knowledge that this is as close as it gets to the regular squat in all the ways that matter.