Speed-wise, there's very little difference between the V-series bows (Vertix, VXR, V3, V3X) and a Triax or Halon with 6" brace height...all are around 340 fps IBO speed. Going a little older back to a single cam bow would put you in the the low-to-mid 330's for most models.
IMO the biggest advancement on the V-series is the Switchweight mod system, which gives you a draw weight range of 50 to 75 lbs just by swapping mods (don't have to swap limbs). But if you already know what draw weight you want and are okay with ≈10 lbs of limb bolt adjustability, V-series Switchweight mods won't be any better for you than the mod system used on the Triax/Halon.