WDHs have not changed much in the last 20 years. Andersen is new-ish, 5yrs old? It hear mixed things about it, but generally better for your weight than 1000 pounds of TW. Others I recommend in similar price range are Equal-i-zer 4pt, Reese Strit Line, and Blueox SwayPro.
4000 pounds loaded means 500-600 pounds of TW. If that 4000 pounds is unloaded, then...
A Tacoma receiver may require a WDH over 500 pounds, so verify. You will notice the loss of weight on the front axle if you drop the tongue on the ball. If you have time, you can try without one for a test drive. I estimate that 500 pounds of dead TW means +750 on rear axle and -250 from front.