At the risk of making things more complex than necessary.....Per Lusk and Kenny, stocking adult fish into new BOW environment can lead to:

1. fish thriving and continuing to grow
2. fish plateau and don't grow much
3. fish decline in new environment [lose weight and/or die]

Lusk had some % of each to expect in recent article regarding adult fish collection/transport/stocking. This is proven science per Lusk and Kenny, so bank on it.

Now, one benefit of stocking adult SMB would be at least getting reproduction going this season and not waiting for age 0 fish to reach sexual maturity [could be a year or two], and even if the transported adult fish don't thrive, you do have a population established via spawn and that generation growing much sooner.

Another benefit is selecting only obviously thriving adult fish to stock from your collection efforts, you're ultimately in control of the genetic selection [IE: Select only fish exceeding 110 WR, etc.]. If you aren't in love with the body condition of the fish, release and keep collecting. So while Kenny and Lusk are obviously correct about tempering expectations on the performance of stocking adult fish, there are a couple potential benefits to consider before you scrap the plan entirely. Even if the stocked fish don't thrive, you still have their genetics established in the pond and their offspring should perform well in the coming years.

FYI: I started my SMB fishery 13 years ago stocking both thriving, adult fish collected [15 fish] AND stocking age 0 6-8" feed trained fish from Rex via Fountain Bluff Hatchery. I'm not recommending you do this, however for me things worked out well. Again, just temper your expectations on the performance of the adult fish if you go this route.