Lexmark International, Inc. Review

I own a Lexmark C5543dn laser color printer. It I paid $250 in 2010 and it is a sm. office or home unit for network type use. It was expensive for toner cartridges from Lexmark, costing about $250 for all 4 cartridges for 2000 pages coverage. I then found a mail order after market replacement toner boxes that last longer and only cost $125 for about 3000 pages. On 6/19/2014 I got a firmware error that would repeatedly return. I contacted Lexmark Customer support. They reviewed the error code, and found one of my computer was sending a print job with a new format that jammed the firmware up. I canceled the print job and the firmware error stopped and the problem ended. The Lexmark support tech instructed me to download the new firmware from the Lexmark website to prevent this problem from reoccurring. I did as instructed. Without any warning the new firmware would not recognize my aftermarket toner boxes, even though they had been working before and were at least 1/2 full. The Tec