What are the VAST versions used

I am seeing following VAST versions are available

VAST 1.0 (deprecated)
VAST 1.1 (deprecated)
VAST 2.0 - http://www.iab.com/guidelines/digital-video-ad-serving-template-vast-2-0/
VAST 2.0.1
VAST 3.0 - http://www.iab.com/guidelines/digital-video-ad-serving-template-vast-2-0/
VAST 4.0 - http://www.iab.com/guidelines/digital-video-ad-serving-template-vast-4-0/

I think reason for using VAST 2.0 to VAST 2.0.1 is below:-

An update was made to the 2.0 Schema because of a small typo found. Please use the schema labeled vast_2.0.1 as the official VAST 2.0 schema. 

1. Which VAST version is currently used by applications mostly ?
2. Will anybody using VAST 2.0 ?
3. Do anyone have sample VAST xml for all VAST versions ?

References:- https://en.wikipedia.org/wiki/Video_Ad_Serving_Template

Europe speaking, VAST 2.0 is by far the most widely used format. VAST 3.0 is also used, but there are many enquiries from all sides on what exactly is being supported (not all VAST 3.0 features are required for minimum compliance).

VAST 4.0 is not used yet and calls for updated not only on the player/parser side, but also on the ad server side. The standard explicitly mentions and upgrade path from 2.0 to 4.0 and I guess many will choose this option.