Its a nicely organised race with a big enough field for company. As said above mostly flat. Think the incline at mile 18 or so probably makes this a less than ideal PB choice.
I think there is hardly anything between the two. It depends what rocks your boat.
It may also depend on what your PB is and what you are targeting. Abingdon tends to have more faster club type runners so probably slightly better for faster PBs as people to pull you along a little.
Chances are with the adrenalin and the competition on the day you will blast those times. 23 seconds in a "race" type event is very little to lose.
Why don't you go along to a couple of park runs and try and race them.
With some of the newer watches / phone combinations you can do this already.
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