Metz,sigma or pentax Digital flash?

Looking around and taking into account all your advice,I know I'll want tilt and swivall, lightweight and easy to use? One that "talks" to the camera!?
I have a LOT more learning to do!!
[Thanks for all your posts!]

Thanks for your comments.
Is pttl worth the extra cost?
Thanks.

Depends what your shooting, I own the Metz 48 & owned the Pentax 360, the 360 was too complicated for me. I only shoot manual so have bought a pair of the Yongnou 560 mk2.

Main reason ws for the 8fps shooting rate, ideal for my kind of shooting, huge power, can add an external power pack, quick to power up.

For the price I think they are excellent, I bought two to use for off camera use...

I can't comment about the PTTL except that's all I've used so far with my 44 AF-1 and it's been good exposure wise so far but I've no used it much to date

I have 1x Pentax 360, 2x Pentax 540 and 1x Metz 58-ii. I would recommend the 540 over the 360 because it swivels, you can disable the timeout and the battery cover isn't as flimsy. But it's more expensive.

The Metz 58-ii is also very good, it can do some things not even the Pentax top model can do, like enable rear sync using manual power output with non-a lenses AND wirelessly control the 3 Pentax flashes as master (so they all fire as slaves on manual, giving me a total of 4 flashes firing on rear sync each on its own independent manual power settings). Pentax flashes cannot do this. But this is pretty esoteric functionality that's really not remotely applicable to 99.9999999% of users.

I made a quick video of the Yongnuo 560-ii on my GX20 filmed on my k-5

The high speed shooting almost keeps up without the extra power pack, with the power pack it will shoot at 8fps at 1/8 power. The flashes also have built in wireless, triggered by the body flash.

Video

These are cheaper too?
I am considering whether to try out a cheap one and see how I get on,or go for it and spend.
Thanks

makes my godox speedlite TT520 sound basic but it still has swivel head numerous intensity settings and body flash slave compatability . But for £26 what did i expect

I think I'll go for the Metz 44af-1. Thanks for all your help and advice I did consider all of what was said.

I did exactly this about a month ago - no regrets and no failures to date.