Can somebody give a brief comparison of TSP and IRAs?
The TSP is similar to a 401K.  If you were hired as a federal employee on or after 1 January 1987 you are under the FERS retirement program. That means that you are eligible for matching. If they will match your deposits then the TSP, up to the matching limit, is a better choice. Skipping the TSP will mean that you you are leaving money on the table.