I have a 5 gallon, and keeping plants in it is such a pain. it was more detramental because they rotted a bit and in 5 gallons, there is little room for extra ammonia etc. in my larger tank, they thrive, and i love keeping them. I have some decent looking fakes that work for their purpose of hiding places.
I think fakes are ok. Esp. for kids and newbies. depends on what you are looking for in fish keeping.
IMO
lisa