I don't see the point of this card - VRAM usage is going to only go up as time progresses. In the UK the GTX1060 3GB starts from £190 to £200,and the GTX1060 6GB starts from £230 to £240. Over two to three years that is not much more to spend,and I would rather not have another scenario like with the 8800GT 256MB,8800GTS 320MB and the various other VRAM limited ATI,AMD and Nvidia cards which well apart over time,and usually in games which pushed graphics somewhat. They all looked pretty decent at release IIRC.
The 8800GT 256MB was a prime example of how VRAM was a big limiting factor:
http://www.anandtech.com/show/2453
Even at a time when 256MB was a common amount of VRAM in older cards,you can see the 9600GT 512MB with only 64 shaders destroying a 112 shader 8800GT 512MB,and they were both of a similar generation too(the 9600GT launched somewhat later and the 8800GT 256MB was a stop-gap card to counter the HD3850 and HD3870 IIRC). At least the 8800GT 512MB was 40% more expensive than the 8800GT 256MB,but the GTX1060 6GB is barely 20% more expensive and also has more shaders too.
Personally I think AMD and Nvidia have gimped their lower end "mid-range" cards just enough,that they will hit issues quicker,ie, the GTX1060 3GB and RX470 4GB.
Edit!!
Plus DF encountered some problems with the 3GB version too(like Guru3D did),and one of those games was Rise of the Tombraider.
Tombraider is one of the most taxing modern games currently,and there is no doubt going to be more in the next two years.
Hitman was more of the same too.
The GTX970 is ahead in minimums.
Latest AC has stuttering too.
Guru3D also showed the frametimes for the GTX1060 3GB in Tombraider and Hitman had more spikes.
The thing is the GTX1060 3GB is also going to limit your upgrade options if you want to get a higher resolution monitor,ie,an ultrawide or qHD one which pushes more pixels,or if you want to use DSR/VSR or push AA.
Plus,what about the resale value of the card - I expect the 6GB version will hold its value much more than the 3GB version as I expect if you are that budget limited you would sell your card on when upgrading too.
As much as I would rather spend less myself on a card,the 6GB version just seems a more consistent option to have over the next two to three years.
In fact I would rather have had Nvidia disable more shaders and had the card as a 6GB one TBH.