I've been using bitcoin since it sold for about $20. And I did a lot of "big things" with my coins back in the days when adoption was shit, and the only place you could spend them was at DNM's. I discovered then that the best way to buy coins anonymously was with cash or using secondary markets, like darknet markets, local bitcoins, bitcoin ATM, etc. These methods ensured you could buy your coins without using an ID.
I found out the hard way that forensic blockchain analysis is real. I tend to keep that in mind when dong big things with bitcoin. Using a good and secure mixer is a necessity not a choice for me. Choosing one is often difficult, so I spread my transactions around different ones. My experiences have been generally okay, except for when I was scammed by coinmixer.net, run by serial scammer moriartybitcoin. I hope that fucker is dead, and his death was/is slow and painful.
I have used just about every mixer out there. from helix, bitblender, bitmixer.io - oh how I miss bitmixer - and most recently chipmixer. And I must say bitmixcoin has surprised me a lot. I took it for another shitty clone of "the mixer with no bottle", that shut down after a little heat from LE. However, its been smooth sailing so far and I rate them A++. I will keep using different mixers, especially the established ones, but bitmixcoin will remain number one on my list until something changes.