I use Serrengetis as well but I would like to emphasise the comment about making sure they are NOT polarised.
What SND said about the screens is also repeated for airborne contacts. If the light reaching you from the other contact happens to be polarised in the wrong direction, then polarised glasses will block it out and you will not see it straight away. Think of wing flash from gliders or other small aircraft which will get cut out by polarised glasses.
Also polarised glasses cut out other reflected light which can reduce or remove your depth perception, particularly on wet or damp runways.
Make sure you only fly with non-polarised gleasses.
MM