Jst got the reply (less than 15 mins after sending it)...

1) They dont have a refferal system in place for VPS customers yet - but they do for A2B2XS customers so if you (or anyone else who reads this) can let me know when they've signed up then I can let A2B2 know,

2) A2B2 have confirmed for me that they DO support Drupal installs.