Need a little help here.

I've been using a G5RV for a number of years for my receivers and it
does a very good job. But I notice that many folks here seem to prefer
a long wire. Is there much difference between a long wire compared to
a G5RV or dipole? And if using a long wi wouldn't a long wire need
to be electrically matched to the receiver? Or, by using a G5RV, am I
essentially using 1/2 of the antenna as a long wire (the center
portion of the antenna jack on the receiver so to speak). Is one
antenna really that much better than the other? As I said, I've been
using a G5RV for quite a long time and I feel I can pick up just about
the same things other folks do; so I don't believe changing to a long
wire would dramatically improve my reception. But then again, I might
be wrong. Any help would be appreciated in understanding the
difference between the antennas a bit better -- if there is any.

John