I've had an M4-2, a very early one, for about 30 years. I've got M6s and others but I do like to go basic, no meter. The M4-2 has been used professionally since the day I bought it. I'ts been soaked, it's been through months of desert duct, it's been dropped and it's never missed a beat. About four years ago It had its first service (by Leica. Solms) and its now going to last a lot longer than me. They're cheap and reliable. Don't hestitate if you can get one.
Roger