If you already have T4, you are not getting much with T5.

this is the jupiter 50 demo that impressed me a lot

jupiter 50

If you didn't know,Jupiter 50 is a little brother of Jupiter 80.
And Integra 7 is Jupiter 80 plus more.

The Jupiter 80 has one advantage: it has 256 voice polyphony, Integra and Jupiter 50 have the standard 128 voice.

And there is one disadvantage of the Integra which keeps some people from buying it: it has a ridiculous 64 storage locations for "studio sets" (= performances or 'combinations' in Korg terminology). The number of storage locations for user tones is sufficient, but if you need more combinations of tones for long playlists you have to find an external solution, e.g. controlling tone changes via IPAD "Set List Maker" or, in my case, by the MOXF master mode.

I've got the Casio Px350. It came out before the PX5S. I agree the action is first rate and the piano sounds are great. It differs from the PX5S in many ways but as a basic piano it is the same but with built in speakers. It also has a very basic arranger section which would be OK for a cocktail hour or similar backround music gig.
I think the PX5S is more aimed at being a Pro Midi contoller/Master keyboard and the 350 more of a all around home keyboard.
For the price either one is well worth it.

The Casio has 256 notes of polyphony, and it is very reasonably priced, and doesn't need a controller as it already has a highly regarded 88 note weighted action.

I really like what I am hearing both in the demos and from those using it.

It can also act as an extremely powerful controller if need be. It has pitch/mod Wheels that I find best for my way of playing.

Plus, there is great followup support.

It gets my vote for sure.

Ian