New to Sniping, Clarification needed.

Alright, ive been scouring the internet for weeks. Trying to find a sniper rifle that best suits my needs, and personal desires for looks and performance. That being said, the M24 style in my opinion is the best looking Sniper rifle on the market. And i know there are many posts about this, but in all the ones ive read, i never seemed to find the answer to my questions. And i have heard different things from almost every site i go to.

If there is anyone that has personally owned, and upgraded, or done work on the rifles i will soon mention, please help me get to the facts. Not just the ranting of ill-informed kids which i soo often find on the internet.

The rifles I'm interested in are these;
Echo 1 M28 $175 ( Source ASGI )
Javelin M24 $175 ( Source ASGI )
UK arms M24 $104 ( Source ASGI )
Snow Wolf M24 $99 ( Source Airsplat )

My main question about the these 4 rifles, is. Are they the same rifles? Everyone seems to have their own theory. From what I've heard The Echo 1 is a mix of VSR and APS2 with some proprietary parts. The Javelin is fully APS2. I have no idea about the UK arms. But I've heard that the Snow Wolf and the Javelin is exactly the same gun. Is any of this true? If there is a difference between all these rifles, what are they? Thank you for your time, i hope I'm not wasting it.