I have been racing about 7 years I'm on my second BB A body and have never used anything but M1 methanol. Its how my first car came set up and , I have not found any real downsides, although it can be a hassle at times. Something no one has mentioned is you cant just jump in the car and run it for a minutes on a cold engine. You must bring it up to 180 to burn off any condensation from inside the engine. If not you will most likely milk the oil with the moisture. Alky binds with water, and that is the enemy when using alky as a fuel. That said there are ways around it such as a primer plus system as mentioned or something similar to run and warm up on gas, and belt driven vacuum pumps to pull the moisture out. I do none of that. I'm just careful. Also have used 3 year old methanol and didnt notice any difference form fresh. Lots of guys down south run it to both keep the engine cool and for the consistency it provides in high humidity as it doesn't rely on atmospheric oxygen like gas. I think if you want to be a competitive bracket racer, and especially if you are in the south, it's a wise move. That said I am running in the north and see plenty of guys on gas printing time slips. Depending on what your set up is you will probably spend a couple of grand converting over properly and thats with a carb not mech . injection. If you do this dont skimp and do your homework or your going to spend alot of money and have alot of problems.