I really like the 2fps option - set the shutter to 360 degrees. You get very smooth, consistent blur. I haven't managed to match the look by using the still timelapse and then converting to video - it's just a little jumpy even when using what should be the same shutter speed. Unfortunately it's 'only' HD and not available in 4K - it would be great if Panasonic added a VFR option for 4K.
You do need a heavy grade ND filter to use this setting during the day - I've got a 1.5 IRND (5 stops) and have just ordered a 3.0 as it was nowhere near enough.