If you're happy to commit to that level of investment (is it really an investment? :wink, then why not.
I did plan to run two systems when I began to buy into Pentax but I found that I simply wasn't using my Olympus gear enough to warrant keeping it. It was a real wrench to sell because the Oly Pro zooms were/are stunning bits of kit both optically and in use. Nice and compact too. Ah well there you go.. I'm getting all sentimental now

Bottom line is I'm happy with Pentax but I also wouldn't rule out trying another manufacturer along side my Pentax gear in the future.

I agree the 7D does look a very nice camera but I wouldn't consider it simply because the weather and dust protection is not up to snuff in comparison to Pentax (or the Olympus E-3).
I've used and will continue to use my K-7 in all weather conditions (when out walking etc) and so far it hasn't missed a beat.
This is a very important consideration for me

Just looking at the exif data I can see with the light house shots you're using quite a small aperture setting. I don't know the Tamron's 'character' with regard to aperture but I would guess you may see a crisper image in the f/8 - f/11 region and still maintain the desired depth of field.
I do agree with Peter though in that viewed normally they do look perfectly acceptable. Have you tried another lens for comparison?

Firstly welcome to the forum

Secondly I have to say 'Cameramarts' are priceless, somebody should sign them up as a comedy act
I just had a gander at their website here... you have to wonder what they are playing at, not a single D-SLR listed for sale

In answer to your question. Myself, I wouldn't hesitate in buying another Pentax. You really shouldn't have any concerns at all, they are still making excellent cameras

Hello George, welcome to the forum

Welcome for the forum Szymon

Welcome to the forum Richard.
Congratulations on your recent purchase

John to quickly answer your question, I don't think any of the RAW converters I have tried hinders the output but I would say they are certainly different (in their output). The thing to do is trial all the popular ones to see what you prefer

Nice camera (and nice review) for sure but I don't see anything ground breaking or stand out here. Cliff's K-7 review is equally glowing (as you commented :wink and it's also not obvious whether he is using output directly or RAW from either camera.

Ian beware of your average high street retailer (as Oggy said in an earlier post). They will deliberately oversaturate and turn up contrast on display sets. Also high street viewing distances and particularly shop lighting don't reflect the average lounge

Better to go to a good home theatre shop for a balanced image / sound quality comparison