My reservation with off body carry... rather like my horseback forays in the past... is you can't step behind a bush or any of a 1000 things that make you step away from your ride for just a moment.
IMHO, you need to be able to discreetly take it with you. It needs to be part of your plan, because surely that day will come. A pouch that you can transfer, sling over your shoulder or other wise take with you is fine.

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NRA LIFE
Reserve Officer 9yrs