5 Speed swap

If you are happy with a large rpm drop between gears, go for it.
A first gear ratio of 3.83 to 1 is worthless in a car unless you’re just cruising. The 1.5 ratio drop to second gear is close to the 833 overdrive. If your car had any performance cam in it, you either have to short shift from 1 to 2 or have acceleration in 2nd be sluggish when you run it to 5500-6000 in first.
It is your decision. It is best to make them with all the information you can collect to know what downsides you’ll encounter

I agree that collecting info is important.

So, to put things in perspective, here are the following percentage of drop for several transmissions:

2001 Mustang GT TR3650A833 ODAX15A833A833R154TKO-500A833 /6A833 HODColorado MA5Solstice AR5
1-2 drop40.83%45.95%39.16%28.34%28.20%40.00%39.45%37.86%40.23%39.78%39.78%
2-3 drop34.00%40.12%38.20%24.29%27.23%33.33%32.32%27.08%37.11%39.38%33.19%
3-4 drop24.24%27.00%30.56%25.37%28.06%23.08%25.37%28.57%20.00%27.01%33.77%
4-5 drop33.00%FALSE21.00%FALSEFALSE25.00%32.00%FALSEFALSE27.10%27.10%

The AX15/AR5/MA5 has about a 40% drop 1-2, which matches the TR3650, TKO500, R154 and Hemi OD from Passon. That's not bad company to be in, and not what I would say is a large RPM drop first to second.

I think the important point with the Aisin trans though is that with the fairly deep first gear, you have to be careful not to over gear the car with a deep final drive. Like @75slant6 said above, an AX15 with a 2.76 final drive would feel like a 904 with a 4.10 final drive, mph and shift RPM wise. But @goldduster318 doesn't like the 3.42 final drive with his MA5. So there is a range for someone.

And I drive a A833OD and while I wouldn't argue isn't the best for a performance build, it is fine for what it is. If someone had limited funds and an A833OD was an option, I would tell them to give it a shot.