Originally Posted by Gruoso 
Let us talk about real prices with the comparison of the OP (K20D vs 40D).
40D+Canon 70-200 f4 USM IS +Tokina 12-24+canon 50f1.8II+ Canon 300 f4 USM IS + Tokina 16-50 = 1100+1100+ 450+ 80+ 1200+ 650= 4580 USD
K20d+ Pentax 70-200 (ops, let us say 50-135 f2.8)+ Pentax 12-24+ Pentax FA50 f1.4+ Pentax 300 f4 + Pentax 16-50= 1300+800+650+200+1250+650= 4850 USD
Of course I am not considering other things such as the flexibility of the system, third party equipment.... I think that some people should start to explain its decissions in terms of preference rather than it terms of price. With the new offers, seems that Pentax is not a bargain anymore. It is no more (and no less) than an excellent system for those that make a given type of photography.
Btw Sven, this is nothing personal against you, I am just using your quote to make a point.
How about this:
50D + 70-200 2.8 IS USM + Tok 12-24 + canon 50 f1.4 + Canon 300 f4 USM IS+ Tok 16-50 = 1300 + 1600 + 450 + 320 + 1200 + 650 =
$5520
K20D + DA 50-135 + 12-24 + FA 50 1.4 + DA 300 f4 + DA 16-50 = 1300+800+650+200+1250+650=
4850 USD
And you still don't have stabilization for all the Canon lenses.
The options are endless. You can buy a Sigma 10-20, DA 16-50, 50-135 and a bigma and do the same with even less money. Shake Reduction adds a lot of value to any kit, you always get more dough for your dollars with Pentax, regarding image quality.
If you're not pixel hungry you could even put a K100D in the equation and cut a good $1000 dollars off the bill
Going lower, absolutely nothing compares in image quality to a K100D with 18-55 + 50-200 + Sig 10-20 at it's price point!