IPMS et al have their rules, if you buildin for a show follow thw rules.
If you are doing a kit review you should build the kit not add scratchbuilt parts.
Kit reviews should, IMHO, include nothing that didn't come in the box with the obvious exceptions of paint and glue. that is the only way we as modelers can compare the relative merits of the reviewed kits.
Most of my tanks have antennas made from wire but i still consider them OOB because I used no AM, scratcbuilt, or kitbashing.