It still remains that the most likely occasions you are to need them are the very occasions in which you can't get them. From a mechanical standpoint, something that takes away resources in character creation or advancement from other areas of the character likely being useless when you need it most is unacceptable.
not really, thy can come get you anywhere just not on corps ground .
wen will thy extract you ?
if you can get out of the corps building you are good for a extraction.(even if it means trowing yourself out of a 5th floor window on the pavement)
if you get shot during a getaway.
if you get into a fight whith a gang .
olso it has to be registerd corps ground, and do you really think the corp wants everyone to know where thy are hiding thyr research/experimental assets .