I've been stopped twice, both times by hand held Gatso's. One time I was driving alone middle of nowhere between Rzeszow and Przemyśl in Poland on a back road just about to enter a small village. I was being tail-gated by a local so I sped up a bit right in view of the police. What luck! They waved me over but as I got near they just waved me on before I could speak with them. I can only assume they saw my UK plates and didn't want the hassle. I'm sure I was speeding but the sign posting in Poland on back roads is non-existing and didn't know what the limit was.
Second time was in Ukraine heading towards Kyiv on the main E40 road. There is a check point where you have to slow from nation speed to 90kph > 70 > 50 which I didn't slow in time for.
Google map location You can see the traffic police with Gatso's. Once stopped I entered their office, did all the paperwork. Meanwhile a few phone calls were made and 20mins later I could go without the fine. Spending time making connections while fishing, shashlyk, and going to the sauna drinking vodka is essential in Ukraine!