Ken already said it

Also use wireless instead of the flash on the hotshoe, the flash on the hotshoe will give you the same light every single time and that gets boring so be creative.

The stofen would not do so much, the way to soften direct light is to enlarge the flash source (that's why they use umbrellas and softboxes) and the stofen does hardly do that since it's made to disperse the light not enlarging it.
A beauty disc or small softbox are the way to go if you want to soften the direct light a bit.

Also try to use what longer shutter times, the flash will freeze your subjects but the longer shutter speed will capture the background lighting and all the colours of the night club so it at some atmosphere.
You could bumb the iso also a bit up if shutterspeeds gets too long but you can quite stretch that.

The 30MB/s can do max 30MB/s and the 20MB/s max 20MB/s there is no difference besides that, don't make it too complicated.

Also don't look too much at the class rating because they introduce the class 10 rating end last year and the 20MB/s was out before that so they couldn't be classed as class 10.

The 20MB/s are more then fast enough so if it saves a lot of money get them.

That's not fully true.
Those numbers are at the maximum zoom settings but if you've the flash on the same zoom settings the difference is less.
At 35mm for example the 360 has 25GN and the Metz48 29GN so the differnce is less then it appears so only with longer lenses the Metz is quite a bit more powerful.

TTL is not supported with the K series DSLR they only support P-TTL and that's a major difference they aren't compatible.
So if you want automatic flash mode then P-TTL or Auto function on the flash the only option.

for under £70 you might get lucky with secondhand flash or else you need to find an older flash with an Auto function. You don't really need to stick with Pentax since the auto-function is controllable inside the flash but it's handy though that the flash and the cmaera share the information so you dont need to input them all the time.
If you want to go fully manual then it doesn't matter what brand, don't get minolta or sony though, they use different socket but Nikon and Canon work without a problem. Watch out for the voltage thought.

I don't see why it shouldn't work.
Vignetting is mostly only a problem with the wider lenses so if you've a DA15 or DA21 you might want to check that first.

Sorry to hear the sad news

Professional course at the fotovakschool.
Not funded/supported by the government so need to earn money for a living and pay the course.

The girl is living in the states, she's living with family their (her mom doesnt like me) after this or next school she will move out (:mrgreen... if it's still serious i'll immigrate if it isn't then New Zealand is on the list.
This winter i wont be able to go to her, hopefully early next year.

I believe quite a lot made some money with some Pentax lenses.
The DA 12-24 is a prime example, it cost now more secondhand then it did new 2 or 3 years ago

But if the price they ask for is close for the going rate secondhand than that off course isn't a problem, they are just shall we say; lucky.

But if you buy now the camera store will get the £25 and not the government and you would have the camera now and not over 2 months

Also now you get £80 back for the body alone or £120 for the body+kit lens. link
I doubt the price would drop that much beginning next year so that you can get it cheaper.
Although the question is how long do you need to wait for Pentax to give the money back

With the cashback action you now have quite a price drop, I think it might take a while for the camera to be below the price it is now with the cashback.

But in those situation you describe you can still connect over P-TTL wireless or smart wireless or however you want to call it.
So if your flash and camera can connect in the smart why why would you still want to connect in the dumb way?

It might be useful if you also have a compact and you want to use a more powerful flash with that.