We tried Del Taco for the first time last month after a friend shared her fish taco with me. My partner loves Taco Bell, but I was bored and wanted something different.
There are similarities between Taco Bell and Del Taco but I think Del Taco wins- more variety is the key. I don't like the bland tortilla chips, though- gotta give that to Taco Bell. Don't like the cheese sauce, either, so Taco Bell wins the nachos battle.
The real winner are the tacos. I love the shrimp and fish tacos- flavorful with a mix of textures to make them interesting. Those soft corn tortillas are the bomb. Now, I know nothing about "real" fish tacos but I thought fried fish was probably not authentic- but what do I know? It's still tasty. It's fast food so I don't expect much.