It depends on what kind of look you are going for. Wrapped headers on bikes are popular on "olskool" style chops that are meant to look purposeful (not show queens) and "hardcore" cafer racers/streetfighters. This is not a look for a bike with a lot of chrome. It is cheaper and easier than chrome, about the same price as a cheepie paint job, but definatly less messy and low maintenance. I have done one bike with a wrapped 4 into 1 (sorry no pics) and here are a few observations/suggestions:
1) unless you are going for an antiqued rat bike look, don't use white header wrap. It will yellow/gray with in a month and just look grungy. If you have a rat bike this will enhance it's tought image, if you have a nice looking bike it will make it look dirty. Black header wrap is available, easy to work with, and will wear a lot better. Plus on bikes with a lot of shiney and flat black parts it will blend right in.
2) It does have a small effect on cooling. considering the pipes on most 4into 1s run right under the crank case heating up the oil. Header wrap helps slow this process. The bike I used header wrap on used to overheat and detonate on hot days in city traffic with 93 octane. After I wrapped the header it ran a little cooler and the detonation went away. Every little bit helps expically when the bike has a big overbore. Combine this with an oil cooler and a few other tricks and they add up to a big difference
3) You don't have to wait for it dry, you don't have to mask anything, if it starts to look funky, you just rewrap it (which takes about 20 minutes). However unless you have 4 drap pipes or stright pipes there will be sections of the 4into 1 exposed (it is really tough to get the whole thing wrapped and can look messy) On my 4 into one I gave it a quick and dirty coat of high temp black paint (I had sandblasted the chrome off) cured it and then wrapped the individual sections and the larger collector leving the junctions exposed. It looked very racebike-ish. Next time I am going to try flat silver and black header wrap, should look boss. To do a complete 4 into one you have to wrap each header pipe as much as you can (start at the collector and work up) and then take a new section and go over the collector, it can look kinda bulky and mummy-ish if not done right.
if your bike looks like serious business and not a rolling scuplture I say go for it. Worst case you can always take it off and re use it somewhere else. From the sounds of it you are building a badass streetfighter so why not, it will only make it looks tougher.
Post some pics when you get a chance, I'm sure we would all like to see it. Good liuck
