Steve, can you tell us what brake pads pass your country's regulations? I can suggest a few pads but I have no idea what the government(s) allow where you live. Also be aware that changing pad types can cause problems all on it own. The original pad material imbeds itself into the rotor and then the new one imbeds itself into the first material but not in a uniform way. This causes all kinds of weird friction related issues depending on heat, brake effort. and generally a uneven feel from brake zone to brake zone as well as very loud screaming that was not consistent. I found it very unnerving. This was on my track car so I am not sure if it would have been a issue on a street car.
I had to have the rotors turned to clean them up. If you do this find a brake shop that knows what they are doing and TALK to the guy who is using the turning machine and let him know you only want the surface cleared. Only remove as little material as necessary to make the surface flat and cleared of pad material. We talked and he believed he could do so at about 5-10 thousands per side. That was close to the minimum his machine could take off repeatedly. If i remember right it came in at a total of 6-7ish thou. per rotor. It worked very well.
Have a look at all the hardware and be sure it is all equally tight. Caliper mount bolts, caliper adapter plate bolts, rotor hats if you have them. The squeal is coming from vibration. Usually that means something is moving around. I use a torque wrench on all this stuff as well as the wheel nuts.