This is a funny thread, and I am going to go out on a limb here and sort of agree with the OP a little, that the 4L30E is not the "best part" of the Isuzu VehiCROSS by any means. That said, I do not think it is a "bad" transmission, it is just a weak point and a severe pain in the boot to maintenance. Thus, many owners fail or their shops fail to do a good job at regular intervals with fluid and filters.
I bought my VX with 24,000 miles on it, and within the first week of ownership, I was slamming gears between 1st and 2nd. I then drained the tranny fluid and my fluid, at 25,000 miles, was BLACK and BURNT. I don't know how this could have happened on such a young tranny, but it is FACT. I have since been using Mobile-1 ATF with good results, changing fluid and filter ever 30-35,000 miles.
I think the tranny, when properly and diligently maintained, is a fine auto tranny for a VehiCROSS in stock configuration. Also, I am pretty sure, the VehiCROSS was NOT meant to be used for TOWING. I also think, it was NOT MEANT to be used for ROCK CRAWLING. So you cannot judge a transmission in a vehicle based on using it for something other than what it was intended.
That said, I do agree, that an Isuzu MUA5 5-speed of sorts or an Aisin auto would have been a MUCH better choice. But we have to remember that it was a partnership with GM that most likely put the 4L30E under our beloved VXes. And it was ALSO GM that screwed Isuzu up in the United States. Honestly, I cannot blame Isuzu for pulling out of the horrid passenger vehicle market in the US at the time. It is sad and unfortunate but it happened to a lot of marques and Isuzu just happened to be one of them.
Bart