I don't know about Stars but I've been told that the Full Tilt 10NL & 25NL deep tables are ridic fishy because people don't adapt to playing deep well enough.
With 20BI I'd stick to 100BB tables and move up to deep when you get a larger bankroll. Make sure you do a bit of learning regarding things like implied
odds, set mining, hand reading, etc, as any post flop leaks will be exaggerated as you get deeper.