Psalter According to the Seventy because that's what I've been using since I became Orthodox and we use it at my church, but honestly I would switch if every jurisdiction could agree on a common translation.
Honestly, we are all supposed to be memorizing the psalms as we live out our prayer lives, pray the hours, attend services, etc. I don't see how ROCOR could be putting out a new translation when they've been using the HTM one for years. What about all of those monks and laypeople in their churches that know so many psalms by heart? Reading these new translations in services is going to totally throw them off. Bishops used to be required to recited the entire psalter from heart before ordination. This seems impossible to us now, but when everyone was reading from the same version and using it all throughout the day, this sort of thing naturally happens without much additional effort. I just think it's a shame that so many translations and alterations get issued so frequently, because it really makes memorizing the psalms quite difficult if not impossible.
Also, I think this poll would have been better if it had specified whether you meant for "Bible reading" or for actual prayer, because most non-Orthodox Christians that I know do not pray the psalms. To simply read them for comprehension might make another kind of translation better, but to actually recite them and attempt to become a part of them ourselves is another matter entirely. It's almost like most people read them to imbibe additional God information, which is a shame.