Hello! The V6 you're looking at is the 4.0L 1GR-FE, which is well proven it's worth. It was in the 4th gen 4runners as well from 2003-2009 and have shown they can tow and tow for miles and miles and....
I have a 4.7 V8 2005 4runner that I'm thankful for, but those with V6's aren't missing much. If you're between two motors, and wanting to tow, the 4.0 is proven tough, and there's that whole saying about no replacement for.....more cylinders?