Ranseur has 950k Base Hull, a 9000k Plant and 16 Guns, while Sarissa has 820k Base Hull, 8000k Plant and 15 Guns. Ranseur is Less maneuverable, but it's actually Smaller than Sarissa, which makes up for lower agility.
On the Other hand... Sarissa is Damn Sexy, while Ranseur is an Star Wars Import. So, I personally go with Sarissa.