Ok - we often have to drive down that (think Middletown/301 area below Christiana Mall) way and it never fails that no matter the time of day or day of the week we seem to hit heavy traffic just into VA. We almost always go down 301 S and hit 95 just above Richmond, I think not far north of Kings Dominion. Anyway - yes there are lights, yes you are going thru some towns. No I've never been in stop & go traffic.
If you do go down 301 from your way, there will be construction (Rt. 1 from 301 in MD connection) on 896 (route from Rt. 1 south to 301 South), or you can take the Middletown exit off of 1 South and go thru downtown Middletown which can be worse than DC anyday! But you'll go by 2 WaWa's, 2 starbucks, a Brusters and fast food places if the kids are hungry. 896 skirting Middletown will get you 1 starbucks, WAWA, Royal Farms, chick fil a, wendys, taco bell, kfc & mc'ds. After Middletown you won't find anything (except us - we live along this stretch) until you hit the Kent Island area.
FYI 95 South is notoriously ugly in the general area of the Rt. 1 exit/DE & MD state lines. If you are coming over the Del Memorial I'd slide right down 13 to 1.
Of course, once you are past Annapolis and headed down 301 south and Waldorf way there will be plenty of places to stop if need be. Plus there is a rest area just before the (Nice Memorial?) bridge over the Potomac.
Enjoy your ride down from South Jersey (I'm Cinnaminson born/Woodstown raised myself

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