I recently installed what is basically that same jack on my 26' TT (probably 800-1000LBS tongue weight) to alleviate the non stop complaining of the 13 year old that had to operate the manual jack it replaced  (honestly, I wanted it too ;) ).  
It's a pretty solid jack for the price - so far, no issues. It does take awhile to go up/down, but for that price, what do you expect? To get "Made in USA" quality,it would have been at least 3x the price, so I decided to take my chances with made in China - so far, no regrets.
You should do it - it makes EVERYTHING easier, (un)hitching, leveling and install load leveling bars are all not a big deal anymore.  I'm moderately mechanical, and it took me about an hour to install it.