Is the Canon EF-S 18-55mm f/3.5-5.6 IS II Lens sharp? This page visually answers that question. Shown above are 100% crops from a lab-captured 18mm f/3.5 test image. Observe the contrast and resolution of these results.
Is the Canon EF-S 18-55mm f/3.5-5.6 IS II Lens set to 18mm f/3.5 sharper than the Tamron 16-300mm f/3.5-6.3 Di II VC PZD Macro Lens set to 300mm f/6.3? The image quality comparison above also answers that question. Switch between the results to see the sharpness differences between these lenses.