So we are clear, you're not really gaining any power through a torque converter, but changing what part of the power band your vehicle wants to start moving(I suppose you might gain some drivetrain efficiency as well, but I don't know for certain). Stall speed is related to input torque from the engine, and the mass of the vehicle. Keep that in mind when ordering, and future modding. Also, as a drawback to the higher stall, your fuel mileage stoplight to stoplight will suffer some(I do not know how much). It won't be noticed on the highway though, so long as it maintains the lockup feature.
*edit* Reworded some stuff and wanted to add.
Another thing you may question is, if you get a 4000 stall torque converter, will you have to bring your revs up to 4000 to actually get the car to move. The answer to that is in the little snippit about input torque. At least, that'* stood true to the cars I've known to get a high stall converter.