Perhaps you should look at why you are killing so many drives. If you are doing continuous burning, heat will become a problem very quickly. In fact, most consumer burners are not rated for continuous use.
Look at your case, can you improve cooling? How about placing a burner on top of the case where it can get fresh air. Lowering your burn speed will also lower the drive temp, it's the RPM that generates heat, not the laser. I find that 32x burn speed really helps keep the drive temp down, and 48x/52x will make the drive hot in just a few burns.
How about dust and smoke? These will kill a drive very fast, but cleaning the laser and mechanisms will help.
Is your power supply up to the task? A bad PSU can kill drives.
Don't use your burner for reading, ripping or scanning. Split the duties between 2 or more drives to reduce heat and wear.
That said, the LiteOn burners offer the best combination of speed, quality, and reliability of any drive. Given reasonable care, they can be expected to produce several thousand burns. Get 2 or 3 and rotate the duties to let them cool down.