From what I've read the science shows it is just as effective as the others and no more dangerous in any way. So what is going on? Eu really having talks with Russia about sputnik? Seriously?
If this is all political then that's hideous. Or are there really issues that the UK are avoiding? 
My belief is that even if there are some issues, it's still far safer than getting covid and risking long covid. I'm in my 30s and I've seen long covid in people I know.
But if I somehow had a choice, I'd actually be looking towards pfizer.