I would NEVER run a 4 point with a suspension seat....that's where submarining comes into possible play. Technically it's possible in any seat, but the bottom cushion giving out really increases the chances given a hard enough frontal impact. I absolutely won't run one with any kind of harness with over the shoulder straps, regardless of points. There's been a number of broken back and spinal injuries over the years attributed to the bottom of the seats compressing, then rebounding the person up into the harness shoulder straps. It hasn't just been been in high speed racing either..there's been a few guys in rock crawlers that suffered injury just rolling over backwards off a climb, with a hard landing.
I'm not sure that high bolsters are really all that necessary in off road stuff for most of us either. I have a set of high bolstered Neon SRT4 seats in my Samurai, and they are nice when I start high speed drifting the thing in the dirt, but on the other hand, I don't find myself sliding in the stock seats in the Blazer either during normal pavement driving or rock crawling. That said, yes, those bolsters are a PITA getting in and out, even though I can easily hoist myself straight up and out of the seat by grabbing the roll cage.
I have another set of Suzuki seats that I pulled out of a junk yard several years ago..I'm pretty sure they came out of an Aerio, with a slight bit of bolster on the bottom and back, that I think will be a great compromise, going into the Blazer. But if I were to cage it, and put in 5 points, they'd be swapped out with a set of tub seats pronto.
