Hey @Arco! So the best card for our beloved GH2 ist the Extreme Pro 95Mbps 64 GB since it seems the high-bitrate hacks were developed on those and thus they are the most stable cards for those hacks. I personally got away with the SanDisk Extreme 32GB Extreme 40Mbps (the precessor of the 80mbps card) when using the most stable patch Flowmotion 2.02. This I would recommend to you, it's a Patch with very good quality, but its not as good as Moon T8 for example. Moon T8 works on those too, bu doesn't span and still crashes now and then.

You have to compromise! You don't need the highest possible quality, also it makes the camera much more likely to crash unexpectedly! That's a big NO when shooting irreversible footage. Keep in mind that club parties are probably lacking good lighting, so you should consider investing in fast lenses or in a totally different camera, since the GH2 is not exactly a light monster. Still best bang for the buck IMO.

Cheers!

FlowMotion was the best for my uses (also in action sports) in my limited time with the GH2.

Flowmotion V2 failed on most of my high action shots. It also would not span on my GH2. Keep in mind that the differences between patches are mostly bitrate and GOP structure. Visually the differences are mostly about how the noise looks on long GOP patches vs. Intra or GOP1 patches. The GOLGOP3 patch solved most of my quality vs. reliability issues. I have done 2hr conference recordings with no recording failures with GOLGOP3 patch. I have had failed recordings with nearly every other patch I have tried and I have tried a LOT of patches! The Extreme Pro 95Mbps 64 GB is well worth paying for.

I'm not familiar with GOLGOP3, but ultimately I went with FM because it was good (maybe not stellar, but good) in every mode- 24p, 30p AND 720/60p. Most of the other patches I looked into at the time were really only "tuned" for one framerate, usually 24p.