Whoever you heard that from couldnt be more incorrect. If its a hydraulic lifter system, then there is zero lash no matter what and thus no clatter of any kind. A solid roller is no more noisy than any other solid lifter.
I have both a hyd roller and soild roller and i think the hyd rollers are pretty quiet when adjusted properly. THe soild well you just have to get used to it.
Man, thats what I'm saying too. My current roller 302 was built to go in my previous '89 GT. It has Crane pedestal rockers(same as '93 Cobra factory rockers) and a lumpy Crane roller cam. The whole thing makes zero valvetrain noise.