First thing you gotta understand is the difference between a bolt on and a slip on... It's not like you'll have an option between the two and one is better than the other.

Some bikes have a bolted-on cannister, others flange the cannister into a mid-pipe that has a junction somewhere - usually in the underpan of the bike.

Check yours... a GSX-R for example will typically have a bolted on can which you can replace with a new aftermarket piece by - exactly as it says - bolting it onto the existing flange.

A ZX-6R by comparison has a SLIP ON system that you replace by buying a system consisting of a cannister and a short length of lead pipe that slips over the exhaust from the header assembly.

Bolt-on cannister:


Slip-on system:


Comparing either of these systems to a full system is less obvious. Bolt-ons and slip-ons allow generally less-restricted airflow and tend to free up a small amount of horsepower, usually at the very top end of the powerband / over-rev range. It won't be a major hit in horsepower, so don't go looking for big gains. What it will do is make the engine appear to be "breathing" better and the key difference over stock is usually weight savings, and of course a nicer sound.

A full exhaust system can be created by aftermarket companies that is able to alter the exhaust gas flow entirely, and therefore alter the powerband more directly - at least in theory. By greatly changing the exhaust flow, as someone has already mentioned, in order to actually ACHIEVE those potential power gains, the intake has to also be set up properly. This means through the use of re-jetting, or re-mapping the fuel system (eg/ Dynojet system, Power Commander) depending on carb or EFI type delivery.

In all likelihood, you won't get proper fueling throughout the rev range after installing a full exhaust system without having the fuel mixture remapped. In fact, the bike might even run rough, hesitate, and not accelerate smoothly.

Akrapovic, for example, in their FAQ section, states that their bolt on and slip on exhausts will usually be able to work flawlessly with the stock fuel mapping on the bike, but adding a full system will require remapping in order to ensure the bike runs properly and takes advantage of the potential added horsepower.

A full system is usually engineered to add peak horsepower and often to fix any "hickups" in the stock powerband caused by more restrictive exhaust and catalytic systems in the stock exhaust. Sometimes this comes at the cost of less bottom-end power in order to reshape the powerband and gain some extra ponies at the top of the curve. Racers don't spend much time around 4000rpm, so they are more than willing to sacrifice that low-end to gain power up top where it is needed. Street riders do spend time down low (some more than others) so you have to look at the type of riding you do to determine if you could honestly take advantage of the extra top end, especially since full systems + remapping equipment + potential tuning time (dyno time) can mean a full system costs A LOT more than just bolting on a new cannister.