Vial/Hylander look like the more structured pairing for a FIP Silver setting: if they hold the left-side initiative and keep rallies in the mid-to-long range, they should control tempo and generate higher-quality volleys. Soleymani/Alipieva’s best path is to shorten points with aggressive return + first-volley patterns, but that increases error risk under pressure. Slight edge to Vial/Hylander in two tight sets if they manage the net battles and avoid gifting free points early in games.