Howdy plaxx...
I appreciate your wanting to get your racquet good 'n squared away so that it can deliver you some premium performance, but if you've never used this hybrid before, your first sampling is only going to be a best guess. Poly mains are often tensioned around 5% looser than softer crosses (often multifiber) in these sort of hybrids, but it's no crime if they're both at the same tension as long as that poly isn't too tight. Any more than 60-62 lbs. is really pushing it I think. Once you play with this hybrid, you'll have a reference tension that will give you an idea of whether you need to change anything next time.
Given your level, I'd also encourage you to consider trying a full layout of 16 or 17 gauge synthetic gut after trying this hybrid. A poly/multi setup is sort of a "premium" string job and its typical price reflects this, but it's also a layout intended for players who hit so hard that they need the poly to sufficiently tone down their power. As a 3.0 player, I really don't see any upside to your using this funky hybrid and you may be spending a lot more on strings than you need to. While that poly can take a long time to break, it actually loses what little resilience it has after maybe 12-15 hours of use.
If you really like this setup, then have a blast and enjoy it. Just keep in mind that you might do fine with a less exotic setup. I string my own frames and I've preferred synthetic guts over other stuff for some years. Plenty of bang for the buck.
