I used a poncho in Ireland. My legs got wet, but my upper body was dry, and it was breathable.

It's also a huge wind drag, billowing out behind you like a cape. Very visible to cars, but it did interfere with me checking over my shoulder.

I don't have the $$$ to buy a good rain jacket + rain pants, so I'll stick to the poncho.

Plus you can use the poncho as a tarp for a tent, and as a privacy guard if you need to change or use the outdoor facilities where people might be around.