That's almost certainly what it'll be, unless I can find a significantly better option.
Does Para make the LDA anymore? That might fit the bill.
I had forgotten about the LDA, but that could work if I could find one.
If I can get STI to put a 5.5# trigger in a 9mm 2011 that would be the leading the pack. But dang that'd be expensive.
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Part of the hang up is "no modifications at all". Even an M&P Pro wouldn't meet the trigger requirement, they're too light. I can't even modify a gun to make the trigger heavier.