What do you mean by government loans? Stafford loans? I know the student loan situation has changed somewhat in the last few years (and I graduated with my first masters in 2007.) But, a Stafford loan is still a Stafford loan. You will ALWAYS do better with government loans, and repayment on them is also much more forgiving, in terms of ability to defer or get forbearances. As another poster said, they are also not credit-based. Now, there is a cap, so if you need more than the max., you'll need to get private loans. But the general wisdom is to always supplement with private loans. The first line of attack is always government loans.
Just to add... I already have roughly $80,000 in loan from undergrad, and another masters. (Sucks, I know... I'm hoping not to have to take anything out for OT.) However, I consolidated my loans to a 25 year schedule and after several forbearances (which raise the overall monthly payment) I pay roughly $600 a month in student loan payments. Yes, this is a lot, but you certainly do not need to make $110,000 to pay it back. Even if I owed over $1000 per month on a 10 year schedule, it would be doable on much less than that, unless I lived in a very expensive area, drove an expensive car, etc.. I think those calculators assume that your student loan payment should not be more than a certain percentage of your monthly income. I'm not advocating going deep into debt when you don't need to, but OTs generally make decent money, even if not the high salaries a lot of people imagine. You get a much better return on your investment than if you took out loans for, say, architecture school (or heaven forbid a non-professional program.) And, don't forget, over the course of 10 years, or 25 years, you will likely see a substantial increase in your salary. Things will likely be tight to start, but the older you get, the more comfortable you get. Yes at the same time people often also take on more expenses, but those expenses do not always negate increases in salary.