I think any of the three are good, convenient locations.  Splitting your time between Tysons and Arlington would be a good option.

Overall if you are planning to visit the area and have been curious about the difference about those three places, I suggest you do a different split. DuPont Circle, Crystal City ( or substitute for Alexandria area) and  Tyson's Corner for max return.

  But this area is complex and you will still profit if making a good decision.  
DC and downtown is expensive for hotels but I think you can get more traffic. In DC you will meet lawyers, lobbyist and such but in Arlington ( crystal city and arlington ), many people are from government or contractors that are easy verifiable or with references.  These areas are good and for the most part in my experience, mainly work for last minute dates.

   Tyson's Corner. This is my area and it's very deverse and is becoming the second city most popular after DC in this area. It is so because many companies decided to camp here ( may tech ones) , and such.  
It has become very busy and not just the business hub but also a social one. But it is still a suburb of sorts as its difficult to walk in this big wide city. Not walking friendly but definitely provider friendly as there are many big business around, as well as small ones and THAT IS WHY People Come Here! Plus there is metro and it might not be super  accessble but it does help!  
Overall and I might be partial here, TS is developing in a rapid state where we all in a couple of years will look at it as downtowns DC!  

Adriana

Hi,

All good questions.

Alexandria is less traveled than Tysons Corner; Arlington sits in between.  If you leave Washington, you cross into Arlington -- by car or Metro -- to reach either Tysons or Alexandria.

Tysons is a huge city-sized business district with lots of traffic, new Metro service (though not much for walking), and access via two major highways (495 and 66) and surface roads (123 and 7).  More hotels, more offices, more traffic.

Arlington has three major business neighborhoods (Ballston, Rosslyn, and Crystal City).  Ballston is halfway to Tysons, while the other two are north and south of the Pentagon respectively, and right across the Potomac from DC.  Parking lots are scarce but Metro is pretty good.

Alexandria downtown is limited in parking, offices, and hotels.  There are hotels along the highway but they are often near government installations (their primary source of traffic) and parking absolutely sucks.  

I live in Alexandria but prefer Tysons for many reasons.  Just one hobbyist's view.

I live in Northern Virginia, but work in DC.  

For reasons other clients mentioned (parking and access to public transportation) my preferences are Tyson's for weekend and holidays and Crystal City or Alexandria (near Metro) for weekdays.  

DuPont Circle is worst for me as far as the popular places go

....guys that don't want to drive out deep into the suburbs.

Tysons for the most part the parking is free and plentiful but traffic can be a p.i.t.a. and DC proper parking can be a p.i.t.a. to find/deal with.  

Also as far as keyed elevators i've been in many in D.C. that are NOT.  For the most part that isn't an issue in Tysons but there is one that I know of that sometimes has that issue.  Arlington in Crystal City anyways parking is free on weekends but not sure about weekdays...most hotels there are not keyed except for 2 (feel free to email or pm me about those).  

Imo split time in D.C. or a 'burb super close to DC like Arlington/Alexandria and then a further out suburb like Tysons area/Fairfax.

Thanks to all of you!