The reliability is no worse than any other car in stock form hell the stock engine assembly of a 1G is good for 11s in the 120mph range reliably but not for no 100000 miles. There arent very many engines out there that you can double their power output on stock internals while maintaining any kind of reliability.

One of the biggest keys to reliability is knowing the fine line between abuse and driving/pushing the car hard. Another thing knoweledge is power literally having a good basic understanding of why you need what and how everything functions together as in part matching for your intended use is very important as well.

If you are new to all this then you are in for one hell of a learning curve. Just as these cars and engines can lay some pretty impressive numbers with a bunch of small cheap mods/bolt ons they can also be destroyed just as impressively.