All great advice I would give. My take on the matter is this:
More power and more "efficient" in the sense that since it's not driven by the crankshaft (via a belt and pulley like your accessories) and thus will not rob you of any horsepower
You also do not see a lot of turbo'd Mustangs and even less 2010s Turbo'd.
Lag time, but in fairness it is probably non-existant or quick. I don't know how the 2010 looks market wise for F.I. but I would assume there currently isn't much so probably a lot of custom fabrication and modification will occur which correlates to more money. Turbos are more expensive to begin with as well (as already stated).
The modular motors have their powerband moved into the higher RPMs so I would expect
the power from the turbo to be a little later. Then of course you could think of it as bigger displacement engine's powerbands occur quickly in the RPM range and a turbocharger would extend that powerband more so you will still have some "go" even at 3500+ RPMs.
Where you have Roots and Centrifugal
Roots style offers instant power the second you gas it, centrifugal also has a "lag time" but is probably quicker than that of the turbo. Superchargers are generally "easier" to install and cost a bit less. The aftermarket for them is great since there are many manufacterers out there: Kenne Bell, Whipple, Eaton, Procharger, Vortech. Of course some may or may not actually carry the right S/C for your car so you'll have to check.
Some HP will be lost in the belt system, the powerband is shifted up more.
Some of this is
opinion and mostly theoretical. I'm sure I'm missing a lot of points as well but that's how I look at it. I'm also not trying to be biased or anything, the decision is up to you and either choice is great. Even if somebody else isn't happy with your decision who cares? It's your car you do what you want with it. Either way you'll need a new tune, but either way you will also get that wonderful F.I. sound
Just throwing this out there but how different are the 2010 4V motors and the 03/04 4V motors? How possible would it be to throw on a Termi's blower on these new cars?