The main difference is that at Bristol International you'll get the experience of operating from a very busy airport with an extremely diverse range of aircraft.
Filton exists on behalf of the BAe factory and, although it accomodates a range of aircraft types and opeartions, it's significantly quieter.
The whole area is a very busy piece of airspace, within the Bristol CTZ and outwith same there's an awful lot of stuff happening of all aviation ilks.
Wherever you decide to go, make the most of what's available and I am sure you'll enjoy it.