To me La Mesa is split into 2; north of I8 and south of I8. I’ve lived in North La Mesa for nearly 10 years, on Lake Murray Blvd. and really liked it. It’s not hip or walkable but it’s safe, convenient and comfortable. All the life’s necessities are within 5 minutes drive. Lake Murray Blvd., Baltimore Dr. and Jackson Dr. are a bit busy but their side/inner streets are really nice residential areas. All the homes are quite old but many well maintained.
I don’t venture to South La Mesa very often, but I definitely don’t like El Cajon Blvd. and University Ave. To me these 2 streets are dangerous and crime-ridden. Downtown La Mesa near the post office and trolley station is walkable but not sure about the crime rate. Homes there are also pretty old but generally not as well maintained.