DBBoolean are actually int under the hood

[lekoala]

I would suggest using this as the default

      SilverStripe\ORM\FieldType\DBBoolean: bool|int

Because internally DBBoolean is a tinyint with 0|1 value, but accepting true/false as well

[Firesphere]

Yeah, might be a good idea.
Just wondering, don't want to break compatibility with older versions. Haven't had a close look or anything, so I might be a bit overly cautious.