Major thing that needs to be considered is the location and size of the damage. If damage is at the edge of the windshield then it will spread fast and will destroy the integrity of the glass. If any edge damage is found then windshield replacement it soon. It will save the life of your windshield.
Automobiles are made so that a cracked windshield can be replaced; they are not made to be repaired. To my knowledge, manufacturers do not recommend or promote repairing windshields they recommend replacing them. A windshield is a structural part of the body and is in place for safety reasons. You shouldn't mess with the overall safety of the car by repairing a glass that is vital to safety during a rollover or accident.
The secret to doing a lot of repairs is knowing where and how to contact people. Mostly it is a function of letting them know you there and able to do the repair. Problem is most people wake up thinking about how to find someone who needs windshield repair.
Prior to spending huge amount on a new paint a little money can be spent on cleaners polishes and rubbing compound just for seeing if grease fix auto glass repair are of any help to solve the problem.
Do you really think that they will stand behind their warranty or will they find some excuse that it wasn't a defect in the equipment, but instead it was misuse and abuse on your part.
Windshield cracks and blemishes can be troublesome. You can never really guess what is going to happen; they almost always start small and end up spider webbing across the remaining windshield. Some rock blemishes only leave chunk of glass missing. If not treated correctly it can turn into a large crack as well.
Windshield repair or replacement is totally depending upon the size and location of the damage and cracks. So, before going for any of these options just consult a glass specialist who can examine your shield and suggest if a repair will work or not. If damage from an accident is quite big then do not compromise your life, as you know better that windshield replacement is a necessity. Just bear in mind that your life is more valuable than anything else.