I have used both maxim and st versions in different runs of the same product and had a significant increase in failure with the st232's I believe that the failures were due to lower esd raitings on the st chips as we were using quite long cables and operating in a "noisy" enviroment. We were interfacing cnc machines for multiple machines making the same part. With the max 232's we had no failures , but the st's would fail within about 3 months. We replaced them with max's and the failures stopped. Moral If you are in a clean environment they should be fine but if not perhaps the costlier max's will be cheaper in the end . Terry