aerobird upgrade
I have not had any signal interference problems with my Aerobird. There are a bunch of Aerobirds in our club and we often fly at the same time, on different channels of course.
Any plane on any frequency can be hit with interference. 27 mhz may be more or less prone to problems in your area as compared to 72 mhz.
For me, there have been no problems and I have over 50 flighs. Nor has anyone in the club reported any that I know of.