Just purchased the Toto Drake elongated toilet and I'm needing a heavy duty seat for it. Is the Ss114 seat fairly solid also flat? I'm a big guy and wanting something comfortable and able to hold me. I weigh in at 400lbs if that helps. I was 450 but with exercise I've been losing weight. Right now I'm looking into the Bemis 7900Tdgsl seat but the dimensions show it to over hang the from 1/8 inch which isn't a problem. Thanks for any and all recommendations.