I used to LOVE this place when I was in high school (which was a long time ago...I'll leave it at that)!, and over the past year or so I've rediscovered it (along with the location off Southern & the 101) and still really like it.
Honestly, I can't think of anything in particular that makes this place REALLY stand out. It's just good, solid food. I normally get a half a sandwich & soup (in a bread bowl). Recently I've had the Southwest Club (I like the raspberry honey mustard) as well as the BBQ chicken, which is also really good.
Normally I get the cheese soup or the cheese soup mixed with the potato. The soup is really good, but for whatever reason it's not AS good as I remember it (that's why I say I still "really like" this place as opposed to "LOVE" it), It's still tasty, but doesn't have as much flavor as I remember. Also, the past couple times I've been here the bread bowls were a bit stale.
Overall, Dilly's Deli is still a solid place for soup & sandwiches. The sandwiches in particular are good, and there's a lot of variety with not just typical offerings you'll see at most sandwich places.