Ok, superchargers could "beat" turbochargers, and the smallest turbocharger in the market could "beat" the best supercharger in the market.
It all comes down to a little somthing called engine VE (volumetric efficiency), which is basically the efiiciency of air being introduced into the engine. Think of breathing.......
For example, you get two ford mustangs (example), both engines were modified exactly the same internally for better VE. If you hook up the right supercharger on one of them, and you install a "efficient" turbo (hence not made to spec for this engine), the supercharged car will out perform the turbocharged one all day on the STREET. When i say street, i say acceleration and pick-up. However, dyno numbers COULD be in favor of the turbo, since generally speaking, turbo's are more efficient.
However, as a rule of thumb, a properly made supercharged engine, will not, and cannot outperform a properly made turbo engine.
If we talk about bolt ons, you are mixing and matching different things, the outcome will be in favour of how lucky you are, unless you purchase a pre-made kit from a vendor (which includes EVERYTHING from software to hardware and everything in between).
There is an old saying, you can achieve 90% of the performance level by going and doing everything you'reself, however, it is that last 10% that makes the overall engine reliable. Hence why tuners sell kits that are not cheap, since they spent hours and hours testing (time = money), and you get something that lasts years (3+) not months.
There is one manufacture out there, that believe superchargers are the way to go since the 1930's, and that is Mercedes-Benze. Hence why the AMG cars are supercharged, which is all good, since their aim for sacrificing some performance for reliablity.
Now, Porsche have been turbocharging cars since the late 60's/Early 70's, which just destroyed all the competition in Lemans, GT1, GT2 and GT3 class races. Then in the 1980, BMW pushed the limits of their engineering, by introducing turbochargers in their F1 cars.
Mind you, F1 cars in the 1980's (specifically BMW's) were cast iron blocks, which ran in at 1.8L and single turbocharged, which pushed out a massive 1,100Bhp (those are what i like to call the golden days of motorsports, today it is all more marketing based).
Overall, superchargers vs turbochargers is an old debate that will never end. If you are the high power, speed killer type, then you are a turbocharged person, who also loves exhaust plumbing and whistling turbo's. If you like to keep it simple, have low end and mid range power and don't mind sacrificing top end and love whining engines for in town and some freeway driving, you are a supercharged guy.