Really interesting, althoug unfortunately only available in Russian: interview with a Russian tanker wounded in Ukraine, recorded in a hospital in Donetsk.
http://www.novayagazeta.ru/society/67490.html
The soldier actually tells a lot of interesting details.
1. All Russian soldiers serving in Ukraine are professionals who have signed a contract. Conscripts were withdrawn from his unit before deployment. But even the professional soldiers could have objected to be deployed on "excercises in the Rostov oblast'", which is from where the Russian military aid trickles into Ukraine.
2. The soldiers were aware of where they would be deployed, although it was never stated explicitly and they were not totally sure until they actually crossed the border. The order to do so was given after a prolonged time which was indeed spent on excercises. However, at least the interviewed soldier saw it as the right thing to do and nobody had to be coerced into carrying out that order. <What he describes seems to be a "don't ask, don't tell" attitude between the rank-and-file soldiers and their superiors.
3. His battailon was deployed as one unit. So not only as a limited number of advisors or in specialist roles (e.g. manning air defence systems), but as a regular unit employing regular military tactics, even engaging in tank-on-tank combat.
4. His unit was some kind of a reserve. Even after moving into Ukraine, they were kept off the frontline. Only when the "regular" separatists saw themselves unable to capture a place, his company received the order to engage. However, he says that there was hardly any coordination with the cossacks fighting for the DNR, which is why he was very afraid accidentally shooting his own allies. His overall impression of the "normal" rebels seems to be that of a bunch of rather unprofessional weekend warriors.