It depends what you are going to do with the car and what boost you are going to run.
If you are going to run stock boost levels and pump gas, the stock turbo will be quicker than pretty much any larger turbo you put on.
If you are going to run alchy and higher boost than pump gas will allow, a larger turbo will be faster, but a stock turbo at 20 psi is going to be faster than a TE44 at 18 psi.
At 23 psi, there is no comparison between the stock turbo and a TE 44, but on straight pump gas at stock boost, the performance is nearly identical, with the stocker probably a little quicker due to is faster spooling.