Celestar340, your comments suggesting me to consider joining BA's Exec Club instead of CX's The Club was very interesting...and I did a quick calculation for my travel in the past 3 months, February to April...

I had, 8 Y (full-fare), 2 J and 1 F roundtrips with CX and BA...all within Asia, short-haul...

With The Club, I'm getting 8 * 1 * 2 + 2 * 1.25 * 2 + 1 * 1.5 * 2 = 24 sectors, just enough to make Silver (oneworld Ruby), the requirements of which is 20 Club sectors...

If I had it with BA's Exec Club instead, I would have gotten 8 * 15 * 2 + 2 * 30 * 2 + 1 * 45 * 2 points, i.e. 450 points, enough to make Silver with BA (oneworld Sapphire)...with Exec Club - Global, I only need 400 points to become Silver, and 800 points to become Gold (oneworld Emerald)...

So, with my flight patterns within the last three months, I would be either Silver (Ruby) with CX or Silver (Sapphire) with BA...

If I want to be Gold (Sapphire) with CX, I need 36 more sectors, i.e. 18 full-fare Y roundtrips...to be Diamond (Emerald), I need 36 + 80 more sectors, i.e. 58 full-fare Y roundtrips...

But if I had chosen BA, I'm now already Sapphire...and to become BA Gold (Emerald), I need 350 more points, i.e. only 12 full-fare Y roundtrips, or 6 J roundtrips, or 4 F roundtrips...

Did I do all these right ?? Seems there's a huge difference there...should I switch to BA now...