2013 Frontier owner here. I've got the 2WD so I can't comment on the 4WD performance, but I can tell you I bought mine from the Toyota dealer. We have a Corolla, which we love, so I went there to look at Tacomas.
I was wholly underwhelmed by the Tacoma. It handled like a hay wagon - loose steering, bouncy suspension, and the seats felt too short/close to the floor (I'm 6'2"). The interior felt cheap and dated. It was not a $30,000 truck, especially in comparison to similarly-priced full sized offerings from the big 3. It was clear that Toyota hadn't done any redesign on it for years, and were just counting on its reputation to sell it. I drove four different Tacomas between model years 2007 and 2013 and felt the same about them all.
And then I saw they had a Frontier on the lot they picked up at auction. How funny, I thought. And after I drove it, I told the salesman that, were I them, I wouldn't have this on the lot. It's embarassing how much better the Frontier drove, felt, and looked than the Tacomas, and for many thousands less.
There's no denying the Tacoma has a (well deserved) reputation for mechanical reliability. However the Nissan VQ series engines have been around a long time. I figured, even if I had to replace anything major, the price difference between the two trucks would more than make up for it.
So far I'm very happy with my choice at about 35,000 miles after purchase. Reliably gets 22mpg, which is my only disappointment. Full-sized V8 trucks get similar (or sometimes better!) fuel economy.
Were I to do it all over again, honestly, I'd probably look again for an Ecoboost F150 or a GM 5.3L. But the Frontier was the obvious choice over the Tacoma.