One feature might demonstrate how complex the subject can be.

Drawing a DB pension uses up lifetime allowance of 20x its starting level. So where transfer value factors significantly exceed 20:1 (ie £20 in value for each £1 of pension), taking a transfer instead will increase the chance of a lifetime allowance charge when the benefits are eventually crystallised.

Did you add that to your last PTOO report?
More views from a different perspective are expressed in an article by LCP actuaraies in pensions world.
pdf report

It should also be noted that while you may consider it a real boon to transfer out the DB scheme to DC the DB scheme is offering what it considers is a good deal to get rid of the liability. Banks have been particularly keen to see individuals transfer their pensions away. By encouraging you to leave their scheme, you should remember there is an actuary considering it a good deal for their scheme.

On the same subject, it has been said that  DB Schemes have turned a corner

The world of DB schemes for the trustees is improving. 
The famous £1trn liability for DB schemes seems like the high water mark, at least while the FTSE recovers from the doom years post credit crunch.

This makes DB transfers a little bit more risky! 

Five factors have been identified by actuaries Henry Tapper.

1. Mortality is improving but not as fast as we’d expected (new mortality figures released)

2. Equity markets are buoyant and bond markets stable 

3. Costs of management are falling 

4. The PPF is thriving 

5. Accounting deficits are benefiting from high levels of CETV take-up

See more here: https://henrytapper.com/