They sound very similar.

I can't imagine anyone rejecting either of these omnis in favour of the other on the basis of the audio quality from their capsules alone,

...however, and it's a very big HOWEVER...

When it comes to wearer comfort, "acrobatic" performance and total freedom from frame or cable-induced mechanical noise, the SE50 is in an entirely different league.

In my experience, (click on my pink pic at left for details) Samson's uniquely flexible, behind the ear "archer's bowstring" method of securing the SE50's is absolutely without peer in terms of the above three parameters, with true "forget I'm wearing it" comfort and matchless ease and versatility of fitting. 

One of my rugby referees emerged from under a pile of twisted bodies, having been accidentally "buried" beneath a rolling maul, with his (fully functioning) mic still in place. (As for his ego, ...aah, well...)

As with their Countryman, DPA and Rode competitors, the tan versions are quite inconspicuous "on camera", with the Samson's not only being roughly half the price of the others, but also far more rugged and readily adaptable.

I'll just append my usual disclaimer, with a view to assisting your evaluation:

I have neither affiliation with, nor particular loyalty to, Line 6, Samson or Sweetwater Sound.

I hope this helps.