"If we take a closer look at the micro-four-thirds lens lineup we will find five telephoto zoom lenses - 2x Olympus and 3x Panasonic lenses including our test candidate. The Panasonic LUMIX G X VARIO PZ 45-175mm f/4-5.6 ASPH. POWER O.I.S. belongs to the new premium d “X” series. The Panasonic lens features an electric zoom lever and an optical image stabilizer ("OIS") as well as 2 ED lenses which are supposed to reduce optical aberrations.
You should be able to find one for around 400EUR which is not cheap in absolute terms but this is roughly in line with comparable offerings from other original manufacturers."