I too like my Pentax cameras (K20d, K-7, and K-5); however, if I didn't already have many very good quality lenses for the Pentax platform I would have purchased Canon or Nikon.
My recomendation for a first camera is to buy used as you don't need 14 mega pixels or more to get good images that will blow up to 11x14 or even 16 x 24 inches. That said go to a reputable dealer (www.keh.com, www.bhphotovideo.com, www.adorama.com) and look at the camera bodies that are last years or even up to three years ago's Prosumer-proffesional bodies and lenses. Don't be afraid to buy used from a reputable dealer especially on your lenses as you will save a ton of money and get good quality.
For Canon I would look at the 40d or 50d and for Nikon I would look at the D90 or better.
Dave
My recomendation for a first camera is to buy used as you don't need 14 mega pixels or more to get good images that will blow up to 11x14 or even 16 x 24 inches. That said go to a reputable dealer (www.keh.com, www.bhphotovideo.com, www.adorama.com) and look at the camera bodies that are last years or even up to three years ago's Prosumer-proffesional bodies and lenses. Don't be afraid to buy used from a reputable dealer especially on your lenses as you will save a ton of money and get good quality.
For Canon I would look at the 40d or 50d and for Nikon I would look at the D90 or better.
Dave