I had 192 whilst trying to get back to the bunch after being dropped on a fast club run a few Sundays ago. In fact for that whole run my average HR was 170 and I few really tired for a few days afterwards
I thought I'd reached a new maximum HR a few months back. However it turned out that I'd brought my VDO altimeter with me rather than the VDO HRM (they look very similar). It turns out that the topography the climb on my training loop coincides remarkably well with my expected HRM readings, that is until it goes over 196 (my max HR) and climbs up to 230m. Eventually I twigged that this was altitude and I hadn't beaten my max HR by 34bpm.