MoFi or Harbeth (used)

Have a look at KEF Reference 1’s. 

I tried to stay away from suggesting things other than what the OP said they are considering, but here goes...

This not a bad recommendation, but the KEFs might be too much speaker in a room that size.  I have the Reference 1s as well as 30th Anniversary Compact 7s and did an extended (about 2 months) comparison between the two.  The KEFs won in my room, but not by much.  The KEFs do soundstaging better (again, not by much) than the Harbeths, which is a plus if you're going to be off-axis.  Overall the KEFs are more dynamic, and are just slightly better in the areas of clarity, imaging, and as mentioned soundstage.  Both are tonally pleasing, with the Harbeths having a slight edge there.

If we're going to toss other speakers into the mix, I recommend trying out the PS Audio Aspen FR5 speakers.  They are a bargain at their price point and have very wide dispersion, which would be a plus with your off-axis situation. PS Audio has a very generous return policy, so you can do an in-home demo and return them if they aren't too your liking.

A friend who has KEF Reference 1 Metas recently did a shootout with the Ref 1s and the FR5s and ended up keeping the FR5s.  While the KEFs are "better" in almost every way, they overloaded his small room while the FR5s created a much larger soundstage in his small space.

go w/the harbeths!

My concern with Mofi, as is the case with all Andrew Jones speakers, is that after the initial intro dealers just start discounting them like crazy which has a detrimental affect on resale value. Harbeth is a known quantity and if you buy used can you always sell them at little or no loss.

Valid concern. There is a 50 point dealer markup so there is room for online dealers to discount MoFi, Focal, etc. I believe Harbeth doesn't allow dealers to discount...meaning if they do they get cut off.

One thing specific to Andrew Jones. He is known for making MK2 and MK3 versions of his speakers. I can almost guarantee you that he is already working on a MK2 version. He is very productive and he will find improvements. Smart business too...releasing an incrementally improved product prevents manufactures from competing with the used market for their own products.

Alan Shaw resists change and will only update his Harbeth line when he feels forced to. that's fine too 

I owned the Harbeth C7ES3 for years and have lots of listening time on the MoFi 8s. 10s and 888s.  

The MoFis have good attack and better bass.  However to my ears they are not refined and the midrange has no magic or bloom. 

The Harbeths are super refined and smooth and have excellent midrange warmth and detail.  Listen with the grilles off.  

When you are used to the refinement and forgiving nature of speakers like Harbeth and Spendor (owned two of each) the lack of refinement that the MoFis present is a deal breaker for my ears. 

soix is right, the Ohm Walsh 2 are terrific for off-axis listening and i have a set in my bedroom.

This said, I own the Mofi Sourcepoint 8 and it is enough bass for my living room, which is the same size as the OP's. The Sourcepoint 10 would have been too much.

One more thing, with patience you will find the Mofi speakers on the used market. Mine were gently used, found on Craigslist locally for $1600.