I stopped to grab a late day sandwich at Wagshal's in the Spring Valley shopping center on Mass. Ave. I have been going there for about 10 years (and have stuck with it during some points of transition)so I can say this with assurance...it potentially could have the DC area's best Club Sandwich. This type of sandwich is my all-time favorite and I have tried MANY to my dismay that are not up to snuff.
Order the "summer special" on French-it is named the "summer special" despite the availability of it in every season. The French bread (from Uptown Bakers) is crispy, fresh, and makes the sandwich out-of-this-world, the turkey is fresh carved (roasted onsite) and the tomatoes this past week were super fresh. I ate half and saved the rest for my journey back home. I ask them to go light on the mayo and add some salt and pepper....Delicious!!!!
PS-I cannot vouch for other sandwiches at Wagshal's but I will stand behind the "summer special".