Finality Of Awards: Investor-State Disputes. ICSID?

One of the key virtues of any dispute resolution mechanism is finality. Will the dispute resolution mechanism lead to a final result in a relatively short amount of time and avoid endless and expensive reviews, appeals and challenges?  If a dispute can be prolonged with a seemingly endless round of challenges and reviews, this creates serious questions about the effectiveness and legitimacy of the dispute resolution mechanism employed.  Investors generally do not want to wait a decade or more for a result or spend the enormous sums that will unavoidably be incurred if endless rounds of reviews and challenges are necessary to reach a final and enforceable result.  And this may act as a deterrent to investment.