A host with Reflector should have these MX records only:
mail1.no-ip.com
mail2.no-ip.com
A host with Backup MX should have the MX records above, but your primary MXs at better priorities.
Example:
| Host | Priority |
|
| mail.domain.com | 5 |
| mail1.no-ip.com | 10 |
| mail2.no-ip.com | 15 |