Longbow build quality is better and it has a Breach Bolt not just a rivet so it should last longer. I've seen examples of the BSA's with really nasty machining marks around the breach.
Only way try them both, both are 12-14 FPE Max rifles so the trajectories will be the same if running the same MV.
Oh nealy forgot getting the scope rail back on to the BSA after stripping can get very bad

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Regards Ora
http://www.ora8i.rivington-riflemen.org
http://www.rivington-riflemen.org