Legacy Audio Classic HD Speakers with or without Sub

Alot of good comments above... getting a sub on these is simply a personal choice.  It isn't a "No Brainer"... These are fairly flat down to 32hz, they also use 2 - 8 inch woofers... There are a couple ideas of Bass.  1 is moving mass air. You can put a 6 inch 3 way that gets down to 35hz side by side with a 15 inch 3 way that also gets down to 35hz and 9 out of 10 listeners will tell you that the 15 is going lower, when in reality, it is simply moving more air.
There are several subs that aren't too expensive that will get you fairly flat down to 25hz. 
For me Normally, if you can place the sub properly, I would prefer the sub, but these could very well be just wonderful without....2 8's move a reasonable amount of air.  
Next, Doug brought up just buying a larger pair... He Mentioned the Focus. I agree, but would also add that between the Classic and the Focus is the Signature.  These are very satisfying speakers and get fairly flat down to 22hz. 
As many here, I really like the Legacy's.  Bang for the buck, the Signature is hard to beat. 
I hope this helps,
Tim

After my demo at the Audio Doctor's I looked at the less expensive Classics you are looking at which I can afford sooner, or saving up for the Focus Signatures, I came with the same conclusion as listed above.

If you can swing it the Focus Signatures are $1,800.00 more expensive and you are getting a lot for the additional money

1: The Signatures use the top of the line Heil AMT Tweeter and AMT Upper Midrange driver. 

2: The Signatures have the larger 10 inch bass drivers and go down to 22hz.

3: The Signatures are taller and throw a bigger soun stage.

Thank you all for suggestions. Initially I was considering the Focus SE's but I believe my room might be too small for the size of them. My room is: 18' 7" X 13' 3" X 7' 5" plus furniture & tables. Also, some ceiling damping. I am able to pull the speakers away from the wall about 2 ft. Side walls are fine. The reason I'm thinking of the Classics first is because of their size based on the relatively same dimensions of the Dynaudio Focus 260's. I like the Dynaudio's and their matching sub but with their relatively low sensitivity I have some edginess when turned up louder and I believe I will reduce or eliminate that edginess with the Classics due to their higher sensitivity & 3-way crossover.

If one's speakers got the goods, then a sub(s) is not necessary (IMO), unless the room is not set up right for those speakers. My solution to add subs recently, was to add fill-in, because I could not provide closed corners for my speakers that benefited from that. This is working for me now in a big way, but the design of the subs were also an important factor. I'm two channel analog, so no goal to produce home theater sound.
Kenny

When looking at Legacy speakers, and considering bass performance and sub or no sub, bear in mind that Legacy measure pretty flat, i.e., unlike some other speakers, Legacy does not boost the mid bass.  Some companies boost the mid bass, so as to give more of that "slam", but that is not necessarily accurate, and may give the impression of more/better bass than the speaker actually has.  So, while the Classic HD go down to around 30Hz, you may still end up wanting a sub, but you could do that later. 

OTOH, as mentioned above, the Signature SE is certainly the way to go if you can swing it.  Think about it this way:  if you go with the Classics, and then end up buying a subwoofer, you could have applied the cost of the sub to a set of Signature SE!