Lots of things factor into this, but here are some simple #s to look at.
Assuming Life Expectancy will probably be about 85 for our generation.....
Total at 85:
($460 @55) $460 x 12 month x 30 years = $165,600
($680 @62) $680 x 12 month x 23 years = $187,680
($33K @3% Int) $33,000 x 1.03 x 50 year = $144,668.77 (hopefully conservative Bank)
($33K @4% Int) $33,000 x 1.04 x 50 years = $234,520.31 (a little better rate)
($33K @7%) $33,000 x 1.07 x 50 years = $972,081.06 (Probably invest in the Markets, in some risky/volitable stuff)
If you were to take it out and simply put into a conservative bank acct, you would probably be better off to leave it in IPERS(if IPERS is still around).
But if you were a risk taker, compounding intrest/returnd can do great things with money.....or help you lose all of it too....
Not an answer, but some numbers to ponder.....