hi, i'm looking at buying a second hand Ashdown MAG-300H EVO head with a matching 300w cab. however the guy selling it keeps going on about having put celestion drivers in it and how improved it is? could someone advise me whether this is indeed an improvement or not? 
PS i'd be paying around £300 for both (about $500)

PS i'd be paying around £300 for both (about $500)
