2 cents.
Nothing wrong with standard cup and core bullets when it comes to the 6.5x55, as they are virtually all designed to perform well within the same velocity window, except one issue - they are made of lead.
Shooting a deer or moose cleanly (heart / lungs without hitting major bones) will still result in some lead fragmentation, and subsequent ingestion on your part, and that of your wife and children of at least some lead. While ingesting some lead is not some horrific life-ending nightmare, lead is a neurotoxin and should be avoided at all costs by women planning on having children at some point in the future, as lead also contributes to birth defects. Lead also accumulates in the body over time, and is difficult to clear.
While I continue to hunt with lead, I am very careful when butchering regardless of the fact my wife and I are past the having babies stage. I have been transitioning most of my hunting rifles to lead less options, and will continue to so.
On the subject of mono metal bullets, such as the TTSX, standard advice is go light and fast - it is good advice, take it. Also, plan on complete pass-through on all but lengthwise shots, even on moose. In other words, be very aware of what is beyond your target (which everyone should be anyways).
Now, before somebody gets all “I done eats lotsa stuff shot with lead, and I ain’t stupider cause of it!”, that is your choice, and as long as people do so with full knowledge of what they are doing, I could care less. However, feeding sausage to spouses and children made from meat full of shrapnel is beyond reprehensible.
Happy hunting.