Sadly MHL was dropped for the X series...
What I recommend you to get is the Microsoft Wireless Display Adapter which is a Miracast receiver for any HDMI TV (also works on projectors and monitors) and I got it after purchasing a Surface Book which uses mini Display Port and it is not very ubiquitous....
The wireless adapter is great for me because it works directly between the Laptop/Phone and the TV without the need of a router or anything else... its WiFi-Direct.
It works great for slideshows and for watching movies, however it has noticeable lag if you try to play a game...
I used to be a loud defensor of wired TV-Out connectivity... and I always used my Android devices with them...
Motorola Atrix with the multimedia dock and microHDMI to TV
Samsung Galaxy S3 with proprietary MHL adapter to TV
Sony Xperia Acro S with its direct microHDMI port
Sony Xperia Z3 Compact with an official MHL 3.0 adapter
But currently I use my Xperia XZ with the Wireless Adapter and its very satisfactory.
