Is Tesla an over-valued company?

I was wondering about Tesla's stock price. Their stock has grown rapidly the last 4 years to as high as $407.36 a share and recently dropped as low as $108 and now it's back to $198. It is the biggest or close to the biggest electric vehicle company in the world and easily the biggest in the US controlling a large share of an expanding market and they seem to do well in most quarterly earnings reports. That alone would seem to give them a pretty good valuation.
But is their value inflated even at its current price? What do experienced investors think. Thanks