I have had several chips and cracks repaired with about 50% success. My insurance (Farmers) will cover 100% of the repair and the glass company will waive the deductable if the crack continues from the repaired area necessitating a replacement later. So you might want to talk to your insurance agent.
88 300E 225K Sold
2000 C230K Totaled @103K
2003 ML320 140K Granddaughters Limo
2009 E350 4Matic Sport 37K Sold
2011 ML350 44K