lol i actually did this a while ago, but only distributed it privately because i had some other strange/improper cubes i couldn't find the source for. they're sized down to 512, pre blurred etc and are 12mb each. they're totally fine for regular max/maya shader use, but anything more than that and you should probably do some work yourself.
the entire package is about 700mb and here it is if anyone wants it. the fh_hdri cubes are converted improperly and are mostly useless but some of them still look kinda cool so i kept them.
edit: just sourced down the studiocubes, they're from this guy's packs: http://zbyg.deviantart.com/art/HDRi-Pack-1-97402522?