I fly (and hike) with a McMurdo FastFind PLB. Small and cheaper than
the ACR, but any good PLB is better than none should you bail out and
end up on the other side of the mountain range from your glider! My
PLB is attached in a "safe" location on my chute (i.e. not over any
risers)

My glider has a 121.5 ELT too.

And lastly, as an amateur radio operator, I have an APRS radio
( http://aprs.fi/#!mt=roadmap&z=11&ts=... =a%2FN8RNW-6
) that automatically transmits my position every few minutes or so
(position, speed and altitude) so my crew can follow my progress.
(Click on the little red dots for track info) Coverage in the areas I
have flown seems very good (especially at altitude) See http://www.byonics.com/mt-rtg
for a radio option.

If a bad event happens, one or all 3 of these should help speed my
rescue.