i finally found the issue with Babble - it simply doesn't offer enough languages !
it offers German but doesn't offer Japanese or Mandarin for example
this is pathetic. Rosetta Stone and Pimsleur offer a lot more languages.
Babbel Spanish course is 275 hours. This is longer than Rosetta Stone and much longer than Pimsleur.
that's a good thing.
on other hand there are 260 weekdays in a year that means if you spend an hour a day ( excluding weekends ) on Babble it will take you a whole year to finish !