SES/SNS/Voice or Pinpoint

We have app running in 3 AWS accounts (dev, test and production), we want the app to be able to send out transactional sms/voice/email alerts for weather conditions. We would also like it to use a local(ish) numbers based on clients locations, i.e. US clients get sms/voice from US number, UK clients from a UK number etc.

Should I use sns/ses/voice directly or should we use pinpoint for this ?

In any of these cases should we get the SNS long numbers out of the sandbox and into production first, and then use the same long numbers to get the voice out of the sandbox and into production ? I seem to have got myself into a catch-22 with support at the moment probably down to my understanding of the documentation.

Can the long numbers (when in production) be used across 3 AWS accounts or do we need to create the long numbers per account i.e. end up with 3 numbers for US clients one in dev, one in test and one in production ?

Thanks