Originally posted by exposed This will be a very open question and I expect some interesting answers. At this point I am using a Nikon D300, 20 2.8d, 20-35 2.8d, 80-200 2.8 AF-S lens. I have read some about the K-5 and it looks great on paper but want to know about real use. I have been a working photographer for 30 some years, and still do a small amount of work but now do work for myself, outdoors for the most part. I am also looking at getting the K-01 so this is my reason for wanting more info on the K-5.
So, how good is the K-5
I think you are asking the wrong question. How good is it? Very, very good, but that goes for the D300 as well. The question I would be asking is about the Delta-Q between the two, related to your shooting habits (in bold above) and the cost of a full gear change.
I am dearly in love with my K-5 and have been shooting Pentax for ages, going back to film. The Pentax sensor excels at outdoor shooting with a large dynamic range. The camera ergonomics are perfectly suited to that environment as well, even when things start getting moist or outright wet. However, Nikon is the king of focusspeed and accuracy. I do not feel the K-5 is hugely behind but that may be due to my subjectmatter. (
500px / Mike Bing / Photos)
You do not state you do a lot of flash photography, or at least you didn't put any emphasys on it, but I'd be the first to admit Pentax's P-TTL is OK, but no more than that and the K-5 has a few quirks in that department.
All in all, you seem to have a very good system, quality-wise, and want to know about another very good system. The differences are not going to be huge, unless you need a particular functionality to which one of the two is better equipped.
As to lens quality: the 50-135mm is absolutely up there with the best of them and at a fraction of the price. The Ltd's are also quite awesome. Glass-wise, you are definitely right in your assessment that equal quality glass will be costlier on the Nikon side.
To me, the answer to your question is a toss-up, sorry.