Triable either way offences are tried in the either the Magistrates Court or the Crown Court
Triable either way offences are the middle range offences (theft, ABH)
Triable either way offences have a wide range of sentencing options
A Plea before Venue was introduced by the Criminal Procedure and Investigation Act1996 and it is where the defendant can plead before the courts. If the D pleads guilty the Magistrates court proceeds to sentencing (if their powers are enough) or commit D to Crown Court. If D pleads not guilty the mode of trial hearing takes place.
The mode of trial hearing is where the Magistrates court decide if they think the case is suitable for them (if they can accept jurisdiction) by considering things like their sentencing powers (max 6months in prison or unlimited fine). If the Mags accept jurisdictions for the case, D then has a choice to trial in the Magistrates or do a trial by jury (Crown Court)
The pros of choosing a trial by jury (Mags Court) are that the judges are more efficient as they are legally qualified and that there is a jury so you are more likely to get sympathy from the 12 ordinary people.
The pros of choosing a trial by Magistrates is that the sentencing is limited to 6 months, it is less intimidating (no wigs or gowns), they are very experienced as Magistrates courts deal with 96% of cases and that they are quicker and cheaper.