The RF range of the CM15A is known to be
poor. This is especially true for the
"thin" remotes, as their antennas seem to be
especially directional (perpendicular to the
remote). Some controllers seem to be better
than others and there are some modifications
that some people have reported to improve the
situation.
Phase coupling is a very well known issue
with all powerline-based systems. Some
people seem to be able to get away without
any additional phase coupling (typically in
very small homes). A passive coupler is
adequate for most people (typically in
average sized homes) while some people need a
coupler/repeater (typically large homes). In
some cases a coupler/repeater isn’t even
adequate (we are talking gigantic houses or
multiple buildings here). There are other
considerations to take into account when
deciding which coupler to use, so it is best
to let the consumer decide which one is right
for them. Once you have decided which is
best for you, you also have to look at
powerline noise and signal absorption.
When looking at the SR227, you have to
realize that this is 20 year old technology
here. There are better options, but they
cost more.
Over all you have to realize that you get
what you pay for.