dynaryder

First,the brakes aren't the only dif between the 3 and 2;the 2 also has a slightly nicer groupo,cranks,and BB. Since you're going to be towing kids,you'll be interested to know the gearing is also lower;26/34 granny on the 2 vs 28/32 on the 3.

The Tektro's aren't high end,but they're not junk either. They're a mineral oil system,which are pretty reliable and go a long time between bleedings(just sold a bike that had gone 4yrs and the brakes were fine). They'll need much less regular maintenance than V brakes,and the pads will last longer.

BTW,you can keep your canti's,and do your own bloody work on them. I run a free bike clinic,and hate working on canti's. Pretty much the only reasons they're still around are because until recently they were the only brakes allowed for cross racing,and because the curmudgeons in the touring forum won't have anything else.