Hope Pentax doesn't regionalise the K mount to prevent cheap imports from Hong Kong

Multi-exposure in camera is so slow that it can be rather useless. You don't keep the 3fps shooting speed which you really need to combine a lot of sequences.

I read the manual several times before I even received my camera...

The micro-switch would be a bad idea as I leave the quick release plate from my tripod on my K10D all the time.

I just saw this thread end remembered that my K10D has SR and is not recommended for use on a tripod. I have been shooting some macro shots that require perfect focus and a still sensor. Well I know what was wrong now, I left SR on when mounted to the tripod!

What you need now is to stop it down to f11 to get a good DoF and sharpness in macro mode. You may need a flash though...

Perhaps wait till you need to make a trip abroad? Or wait for any family to visit?

How much is shipping to Argentina?

I know how you feel about prices. Here in the UK we get a direct $ to £ converion 1:1 on products. So they are actually twice as much or more than in the US

There are few things that are cheaper.

I found a second hand one today here in Leeds (UK) for £125 (~$250US). I think the Tamron 70-300 may be a better lens. The edges of the Sigma are softer than my Pentax 50-200!

The centre at 300 is still sharp, 200 is fine and less than 200 is good. Nice to have the 2:1 magnification on it as well. It isn't light though as it covers full 35mm frame.

Also found a second hand Sigma 10-20 (don't remember the price) and a K100D with 18-55 for £225. I wish I had that 225 as I love the size/weight of the K100D.

Automatic aperture control only works with A series lenses or above.

M and K lenses you have to use the aperture ring to set the aperture, press the green button to stop down and take a reading and then adjust or take the shot.