In the fast-moving portable GPS navigation market, the one constant is change. The latest move comes from Garmin, who has trimmed its car navigation line by retiring several, well-rated models including the Nuvi 350, 360, 370, 650, 660, and 670. The Nuvi 660 is a CR Best Buy at $350. A premium, full-featured device, the Nuvi 660 combines performance and portability with most available features, and it is a good choice for power users who can truly take advantage of its rich feature set. Despite their early retirement, you’ll likely still find these models for sale—at least for a while—in stores and online, possibly even at discounted prices . And speaking of discounts, Garmin has lowered the price of two other Nuvis: the 750 ($399 from $500) and the Nuvi 780 ($599 from $700). Be sure and check out our GPS Ratings (available to online subscribers), which are bigger and better than ever. We recently tested nine new GPS devices (including the Garmin Nuvi 205, Nuvi 205W, Nuvi 255, Nuvi 255W, Nuvi 880). We also updated how our Ratings are scored and displayed to better represent the factors that matter most to users, informed by a recent survey of over 2,000 GPS users, feedback on our Cars blog, forums, and user reviews. (Turns out, we’ll be updating our pricing soon to reflect this latest news.) Garmin has also just announced their roll-out of seven new Nuvi GPS models. We’ll be posting more on this soon. —Desiree Calamari