Also did some benchmarking on my Macbook (with a SSD and memcached running on localhost):
Checking egw_cache_memcache:
0 checks failed, 100 iterations took 0.480 sec
Checking egw_cache_apc:
0 checks failed, 100 iterations took 0.025 sec
Checking egw_cache_files:
0 checks failed, 100 iterations took 0.826 sec
--> APC is by a factor of 20 faster then memcached, which is double as fast compared to files on a SSD