Well if you really want to use it, then sure go for it. Any Pokemon with grinding and training can be used in-game. Use whatever you like; I even used Ash's Hoenn team from the anime to beat the game so yeah Magcargo is a lot better as compared to the non-evolved Pokemon I used in the game. Decent enough defenses good special attack,
but yeah as sumwun said there's not really much going on for it due to its weaknesses and speed. But still, I think you can make it work if you really like it:)).