Purchase and use as pure a methanol as possible. Use methanol from sealed containers. VP M1 methanol is a standard as far as quality and purity. Some methanols contain additives which can effect components in a detrimental way.
See the methanol section in this link
VP Racing Fuels
The methanol other then M1 contains additives = will effect pump seals and diaphragms and or other components.........failures suck and happen when you least want it or you could get leaks and if the supply is mostly methanol or 100% it would be like a gas/fuel leak.
Some race shops are not careful in preventing cross contamination so be careful that you are not filling up 5 gallon containers from a 55 drum = just a little cross contamination from the transfer pump being used between different blends can cause issues.
The methanol you buy and want to use should look clear and not cloudy.
Handle with care. Check the MSD sheets on methanol, Its very bad stuff to be breathing or otherwise handling like a generic fluid.
Young kids having access to this stuff is a disaster waiting to happen so if have kids and a garage keep it locked up and make sure the wife or other adults know whats in the pail/drum and that its not gas or weed killer....it is potentially much more dangerous = just needs to be inhaled for problems.