I own Nikon, Canon, Olympus and Pentax (in the order of purchasing) and plan to purchase more name brands that are worthwhile to try such as Sony and Fujifilm. Canon is my main wagon which carries me the longest way so far. The collection of the lenses I own are mainly Canon as well. The gears I have so far are primarily budgetary except a few lenses of medium pricing such as wide-angle lenses. My goal is to, someday, write a photography book with a chapter devoted to "how to produce stunning images using nothing but budgetary gears."
The reason I purchase Pentax gear is the high feature-to-cost ratio. For example, recently I purchase the kx package with 18-55 and 55-200 kits for less than $270. The price is on its way dropping. The 55-200 daL actually well exceeds my expectation (see my review at
SMC Pentax-DA L 50-200mm F4-5.6 ED Reviews - DA L Zoom Lenses - Pentax Lens Reviews & Lens Database). I also acquire FA 100-300mm 4.7-5.8 (by the time of writing this) and anticipate some surprise. K-x performs acceptably well in daylight. The image is clean, although the IQ is not so good in nightime (It actually does not deserve the high remark for the high ISO performance) Nevertheless, for little money, you got so much features packed in one body with surprisingly sharp mid-telescope lens. You really have nothing to lose.
Overall, so far, although Pentax is not my most favorite gear, its feature-to-price ratio indeed is top ranked in my humble, unbiased opinion. Image quality wise, however, I think Pentax still has some room to improve. For example, K30 that many Pentaxian are raving about, including the perfect score 10 for the IQ rated in this forum, actually has pretty bad jpeg engine that produces horrible shadow recovery image (see
https://www.pentaxforums.com/forums/pentax-k-30/231416-k30-jpeg-engine.html). Nevertheless, I believe it will catch up with its peer competitors eventually.