All I can offer is that I have been VERY happy with my DIRECT loans. I also feel more secure with a federal debt because it is not based on credit history, and (as is true with most government programs,) they don't change very swiftly. As long as I keep my eyes open, any changes to the program, including interest rates and deferment issues are readily available ahead of time. Private banks are rarely so forthcoming.
However, if you are going to be consolidating, keep these things in mind:
#1-check the current interest rate. If you took out your original loans more than 4 years ago, you are almost certain to get a better rate.
#2-will you be consolidating loans with a significant other? If so, be careful. Most govt. loans stipulate that upon death or permanent disability, the loan(or some portion) is forgiven. If you consolidate with a spouse, that option is forfeited
#3-check to make sure your deferment options will still stand.