It's fine in my view. A lot of people here (and elsewhere) complain about 'industrial sections' on camino, especially this section. My experience in general, and on this section in particular, is that there are far fewer industrial sections than is often claimed. Leaving from Lisbon, there is one smoke-stack, industrial complex reminiscent of the nuclear plant from The Simpsons that you will walk past on day two or three and it looms large for a couple of hours; I actually flew over it this week while leaving Lisbon and chuckled to myself as I remembered walking past it.
Apart from that, basically, the outskirts of Lisbon after Oriente aren't amazing but the new route avoids a some of it; Vila Franca de Xira and Azambuja are nice towns; from Azambuja to Santarém it's dusty and shadeless and can be hot; Santarém is a very nice historic town, and from Santarém to Tomar it's quite nice alongside the Tejo (Tagus) river. All in all, this is still a rewarding stretch of camino in my opinion. The part of the CP from Lisbon to Porto that I preferred less was Coimbra to Porto, which is extremely suburban.