For me (based in Germany) it is light and shadow.

My plans were: LTG and then try out EK.

Positive:
- I can try out EK now and get points and SCs on QF coded flights
- I get Status Perks on EK

Negative:
- Fares with QF-Flightnumber tend to be much too expensive if you travel to SIN
As I fly BA quite a lot
- BA/QF codeshares eliminated
- No more minimum points or status bonus
- SCs stop counting for loyalty bonus
- No more Lounge Access for QF-Club (which kicks in when the PG expires soon).

On my regular flights to LHR I really lose much.
On my flights to Australia it is a bit more choice.
On my flights to Asia it is mixed.

Overall I see it more negative than positive. Loyalty to QF is definitely decreasing.

So now: Stay until reaching LTG - then reconsider. But as things go I will then reduce my activity with QFF.