Supreme Court Term Limits?

The idea of lifetime appointments for Supreme Court Justices being outdated has been floating around for awhile. Now a new bill proposed in the House seeks to limit their term to 18 years. This would assure a President appoints two for every four year term, instead of fate deciding. Current justices would be exempt, and the cycle would begin with new appointments. Do you agree a change is needed, or is the current system working?

*For International CCers, or Americans that need a refresher: The Supreme Court of the United States (SCOTUS) is our judicial branch composed of 9 judges who have the responsibility of interpreting federal laws based on their reading of the constitution. They have the final say after all other appeals have been exhausted. Appointments are done by the president, and confirmed by Congress. They serve until they either choose to retire, or die in office. Their terms are currently averaging around 25+ years.