Toy Dealership Flush on 2008 V6 Sport

Should I anticipate issues after a Toy dealership trans flush? Service history is pretty consistent on toyota.com/owners from 6k to 108k but stops in 2017 and there's no specific mention of transmission service. I've had the vehicle since August, currently at 156k, and performed all the other fluid services myself. I'm debating whether I should do a pan drop drain and fill myself or have Toyota do a trans flush. I know our drain and fills are a bit more complicated so I've familiarized myself with the procedure using a couple of guides on the major forums.

My goal is to get it in optimal shape for longevity. Cost isn't top priority, performance and longevity is.

Dealership Pricing:

(parts) Trans filter, pan gasket, o-ring and crush washers = $175

(service) Trans Drain and Fill = $175

(service) Trans Flush = $289

https://preview.redd.it/60wx9m6dysde1.png?width=1664&format=png&auto=webp&s=d7befcb767bee29e84df0e89d8d741b0b6a718ff