PIC Microchip interface with PC
The use of the USB to Serial Adapters work well if you use the latest drivers. I have had no problems what so ever when using the types of adapters based upon the chips from a company called FTDI. One reason that these adapters seem to work better is that the company directly supplies the drivers from their web site. They also put a lot of energy into maintaining their drivers and keeping them proven via the Microsoft WHQL certification process. The same cannot always be said for other small or "no-name" vendors and thus the reasons that unreliability and incompatibilities are seen from time to time. 



An added benefit to the use of FTDI based devices is that the WHQL certification of their drivers gets them "in the box" with the Operating System. This means that on newer versions of Microsoft's OS that the serial adapters can truly be plug and play.