With the varifocal I could easily read my GPS unit and could quickly see that despite the good signing I'd missed a turn. No problems to whip my phone out and check position on my OS map app.
The AG100 has 4 timed stages, the last involving a long push up a steep muddy, rooty hill, it's not nice. And it is in a dense wood. No steaming up at all, brilliant. By this time in a longish ride any riding glasses would be on top of my helmet due to fogging, muck etc. Not the Rad8s, although naturally there was some grot in was just track dirt, vision remained good until the end.
Very pleased customer.