VOLVO'S S70 sedan has been overshadowed over the years by its popular station wagon stablemate, the V70. The reasons are various, but the chief motivator has probably been the rash of more svelte, better-performing and generally more appealing product from other European manufacturers. The S70 remains a solid, safe and well-built car, but it lacks the sparkle buyers in the entry-level prestige segment appear to be looking for. Where the V70 wagon has become something of an icon in its segment, the S70 sedan is quietly languishing.