Nice find there. This guy has been making some great strides in the field of automated trading.
MT4 does have its limitations especially when it comes to the strategy tester but there are some good points about it too. You pretty much can do anything with the MQL language and it's a pretty affordable way for the average trader to venture into either full automated trading or semi automated trading (trade management etc).
You can still keep it.... I personally don't auto-trade..... If i did I would certainly use something other than mt4, say.... IBs API, or Oanda's API... sorry but I just don't trust mt4.