My original idea was to solder 2 jumpers to increase their electrical reliability. But after a trial I realised that my 58 years old eyesight won't let me do it because it's a very delicate task. So I have no other way than to use those switches without the jumpers. For how long will the switches work before deteriorate ? after a couple of months or 3 or 4 years ? Any estimate or some real data ?