Hi, I need a ball valve to fit onto my 22mm overflow pipe. Toolstation have three different ones - two are 'push fit' the third is John Guest. The prices all vary. Links below Questions: 1) will they all work with solvent weld over flow pipe? 2) why the price difference, will the cheapest work fine? I need 15 of them so cheap is good! Cheapest pushfit expensive push fit even more expensive John Guest Thanks!