Air Intake upgrade. Worth it?

Question: I have been contemplating putting a Hypercharger on my 1996 Vulcan 800. I know that to truly see hp gains you have to re-jet the carb and it's best to upgrade the exhaust. I already have cobra drag pipes which sound great and move plenty of exhaust. The carb has already been re-jetted to accommodate them. So will I need to get new jets yet again? And is it worth it to go ahead and bore the engine and get new pistons and cams?  

I put an upgrade on my VN800. Thunder Air, basic K&N air filter, adjustments on the carb, new jet.
Before the change, it took 5 sec from 30-50 in 3rd gear, after, it was 4 sec. Before, the engine lugged at 50, after it was 40.
My biggest mistake was having the main jet installed, since I hadn't done anything with the exhaust. Mileage dropped like a rock at higher than 75mph (I had a 17/38 sprocket set).
If you just do the intake, don't install the main jet.
What you get is a chunk of torque, what you miss is Hp. I almost never missed the ponies, except when I was in rush hour traffic, and I was doing over 85 in the right hand lane.
Since I never did it, I can only guess. I suspect that the torque would go down somewhat if you actually do the exhaust mods.