I have it in addition to my m43 and use it more with manual lenses as the focus peaking helps. It is the smallest viewfinder camera and prefer its grip to Oly cameras. Focus is faster with m43. The native Sony lenses are growing, but still not strong on the tele side. Here is a good database of available lenses: Sony NEX lens database
Only long tele Sony 55-210mm is a bigger lens then Oly 75-300 with 55% reach of Olympus. I see a few people shoot older manual teles for birding with nex but there is no af and no size reduction from dslr lenses...
Actually the Nex 6 has a lot to offer. I use legacy glass most of the time and its extremely efficient to work. The Sigma 19 & 30 should be against the law they are so good.
The camera is very easy to setup and easy to find what you want it to do.
My friend sent me an M240 but I don't like it. I didn't like the Mono either, here's where the Nex excels.
The Nex6 images look very photographic. By that I mean, they don't look like Digital representations of a photo. I hope you get this.
There comes a point when photos are to detailed, too much resolution, too artificial.
The Nex6 and other Nex's are not that way.
I think that's the most important thing with photography today.
I really like the camera and better then my GR but the GR is learning from the Nex.
Good luck in your quest.....
Thanks for asking this question. I am in the same quandry and trying to decide on a mirrorless camera. There are so many good choices and yet they all have their compromises. The Fuji X-E1 tempts me, but I'm not sure what to make of the sensor, especially after reading Sean Reid's thoughts about the X-Trans sensor (not to mention the focusing issues as exasperatingly described by Lloyd Chambers). The new E-P5 looks great, but I'd prefer the larger APS-C sensor. Finally, the NEX-6 with the Zeiss 32 seems like it might be the best compromise between the two.
While there is some speculation that Fuji will add Focus Peaking in their upcoming firmware update, the NEX's Focus Peaking feature evidently makes it extremely easy to use manual focus lenses. I'm curious about buying "something" from CameraQuest (voigtlander?) in order to to give this a try on the NEX.