A person by the name of Varun Vista composed an overview of arguments on internet, some of which I have copied here - worth (at this point in time, 21 July 2014) to copy, as the Russian claims are so ridiculous that one cringes.
Well here are some facts:
Russia claims a Ukrainian Su-25 shot down MH17.
1) MH17 was traveling at 33,000 feet.
2) The Su-25's is a ground attack jet with an altitude ceiling is 23,000 feet.
3) The Su-25 carries a single tiny AA missile incapable of air-to-air attacks.
4) The speed of a 777 at that altitude would outrun a SU-25
5) There was no comms from MH317 saying it was being trailed. (Black box will prove)
6) Someone from a Kremlin IP has been editing Wikipedia to increase the Su-25 ceiling. (They really are incredible these guys)
So ..... by the laws of physics, gravity and basic science the Russian theory is so impossible it's laughable.
Now let's layer on some additional facts.
1) There was a Buk SA-11 launcher pictured at Schizne, right by the shooting (deep inside rebel territory).
2) BUK SA-11s have complicated fire control systems - it's not one button, but tens of buttons you need to sequence to paint and intercept a target - not exactly the capability of an untrained peasant mad at Kiev, not even peasants who apparently have Grad launchers, T-72 tanks and MANPADS in their tool sheds.
3) Three BUK SA-11 launchers were pictured returning to Russia 24-48 hours after the incident.
4) A BUK SA-11 shot down an AN-26 just a few days earlier (which makes particular sense because AN-26s in this case are civilian registered, so if there was an IFF you'd have to turn it off ... and then paint a 777 without realizing it was civilian)
5) Pro-Russian separatists control the crash site and within an hour of the MH17 shoot down, they were boasting about shooting down a Ukrainian jet.
6) Pro-Russian separatists have denied OSCE monitors access and obstructed their efforts.
7) The black box was stripped off the wreckage and said to be going to Moscow before now apparently reaching Donetsk..
8) The behaviour of both terrorist rebels and Putin oozes "guilt" - truly uncivilized and despicable.
9) Putin could have stopped the circus at a snap of the fingers, but didn't. At worst he could have closed the border and
recalled FSB and arms; the result would be a total collapse of the rebel circus.
Oh and as for the theory it was Putin's jet they were aiming at... there must be something really powerful in the Donetsk milk that helps them see paint markings on planes flying 10km up in the sky.
Are you getting the picture? Russia's rebels shot the plane down and to date has blustered, obfuscated and done everything to hide its role and "useful idiots" (yes that's Putin's term for his foreign apologists!!!!) have swallowed the most ludicrous stories.
With a unanimous Security Council ruling and the black boxes in Malaysian hands, we are at the level we should have been on Friday, a day after the plane was ruthlessly shot down.
No, it was not a disaster or a terrible accident - it was a terrorist, criminal act; bloody murder.
That's what these East Ukrainians stand for - and let's not forget the disappearance of wallets, credit cards and vital clues from the crash site or the fact that a guy by the name Yanukovych and his 2 corrupt sons still sit in the background and pull their criminal strings using the robbed $$$Billions from the Ukrainian people.