How heavy? 43.6oz / 1,235g, without the lens hood. Ouch. To be clear, quality 135mm f/1.8 lenses like this are heavy, but the Viltrox is another level; it's about 25% heavier than the Sony and Nikon ...

52MM Tulip Lens Hood 7. 52MM Lens Cap 8 ... looking to elevate their photography skills Compatible With Nikon D3200 D3000 D5300 D5000 D5200 D3300 D90 D80 D40 D40X D70 and all 52mm filter thread ...

So in terms of flare, the lens will probably survive without a lens hood. Distortion is very low, measuring +0.16% pincushion. This is almost rectilinear and is better than many macro lenses.