As a follow-up to a series of questions I asked a while back..
I've now used the Mini for several adventure races that mandate a tracker (out in the field for multiple days to several weeks duration) and I'm pleased to say it has not missed a beat. Link it up to organisers tracking system (ie. provide them with your raw MapShare URL), use it in it's extended mode (or whatever it's called, the one where the screen switches off and it powers itself fully on for each update then off again), turn it on at the start of each day, turn it off at the end of each day, rinse and repeat, charge every 2/3/4 days depending on how long been riding for.
Usually it's a SPOT that is offered for hire to participants that don't have their own tracker - in each race there was problems with some of these (possibly user error!) while the Mini performed flawlessly. The SPOT has the possible advantage of running on AA batteries and that seem to last around a week, whereas the Mini is yet another thing to charge from often scarcely available power, yet it lasts so long on a single charge I never found this a problem in practice. Also the SPOT can update every 5 minutes whereas inReach is 10 minutes, though over a multi day event this made little difference (once your followers got into the grove that your position updated every 10 minutes vs. others every 5) and in fact I'd happily take the seemingly increased reliability of my say 5 or 6 updates an hour (coverage dependant) vs. others sometimes doing 12 updates an hour then going 'dark' for a few hours.
My only wish would be for a flashing LED or something to indicate it was doing its thing - I'd often manually turn it fully on mid ride just to check it was working (100% always was) which seemed a bit cumbersome.
All in all: thumbs up, recommended for this use case.