hmm....
live plants look better than artificial plants, yes.
artificial plants easier mantinence (but really, don't be lazy about it

)
live plants absorb ammonia, nitrite and nitrate
live plants create algae (true? seeming that plants and algae are really the same thing.)
since live plants absorb the stuff, if something goes wrong, the plants die and the stuff gets released. So dead plants=remove asap or regret it!
as for health of the fish, as long as it's hiding spaces, nothing really different to them...
you need CO2 systems for live plants and full spectrum lighting and stuff.
but if you still want to go live plants, then the recommended substrate is flourite...
but java fern's roots MUST BE ABOVE SUBSTRATE or the roots die, the plants die, the whole releasing thingy happens, fish unhappy and stuff.
but live plants add soooooo much beuty for your tank. They also release oxygen into the water, in return for taking in CO2. at night when the light's off, the absord oxygen to create CO2 (respiration

)
but i chose artificial, since i couldn't get the CO2 system set up... but I really have to say for myself, it looks cool
would've looked better with live plants, tho.
btw, if you see plants in a tube out of the water, roots in some gelatin thing (product called sometimes snail-free) STAY AWAY FROM THEM!
btw, if you're going artificial, you should go gravel. flourite is dirty but has lots o minerals for the plants.