1.6 = cheap, simple, safe (parents/insurance), and hopefully reliable enough to not have the coolant lines break off 500k from home like my 1.8t...
1.9 = more expensive (in Canada) possibly more reliable than a 1.6 but I'm not experienced enough to decide one way or another, and slightly heavier which is a downside when I have to drive up to Edmonton about twice a month with some essential engine component in my car
I'm also not looking for huge power, nor do I have the money or time to turn around and track down a 1.9AAZ to get put in her, so, 1.6 it is.