We’ve got one and can get the tandem in whole, albeit at a bit of an angle. We can easily transport 3 people and bikes (combo of tandem/road/MTB) and luggage inside.
In the Grand (ie LWB) version, you can unbolt and remove the rearmost seats,but the second row fold “flat” – that is flat if you also have the third row, otherwise it’s a few inches step between the real floor and the seat backs. In the SWB one, I believe, the second row seats roll forward to give a flat load area. The third row aren’t really made to be removed and replaced (star headed bolts they are quite awkward to carry), so it’s not something you want to do too often – by contrast, our previous car was a Pug 308SW in which the two rear rows were designed for this.
I got the Tourneo because my wife baulked at the full van look, but the downsides include the seats situation, lack of flat load space, lots of interior trim to get tatty chucking bikes in the back and finding ways the secure bikes. On the upside, the seats are quite comfortable, I’m told, and it’s a bit more car like – probably quieter given the carpeting etc.