PEX or Soft Copper

I need to replace all my cold water lines in my kitchen sink. Long story, I used low pressure plastic lines, taking some's advice, realize now that they will not suffice. After the ball valve shut-off, I used plastic compression fittings and t's to go to the icemaker and dishwasher lines. Can I just replace the low-pressure lines with either soft copper or PEX? They are the push-in type fittings. Which would be easire/more reliable/require less tools?? I assume either option can be just pushed into the fittings, their usage is listed to be used for any plastic or copper line. Thanks ahead for anyone's help.

pipes

Use stainless steel braided supply line with compression nut ends. For the DW either change the wall valve to one with two openings or find a Brasscraft "Add a Tee" that secures to the valve outlet and gives you a good place to connect the DW line.