I am a rainbwofish nutter, but I would hesitate to say that they are "ideal" for planted fish tanks. I keep and breed over 20 species and while some are fine, many really do have a taste for plant matter and will nip at your softer leaved plants like Downoi, Blyxa japinoca. You can mitigate to a degree by providing plenty of plant matter in thier diet, but not stop it altogether in my experiance.
Still this is what I do, keep rainbowfish in planted tanks
I posted these on the UKAPS site, some examples of a few rainbows i keep:
M. lacustris
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M. trifasciata "Goyder River"
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M. splendida rubrostriata
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M. inornata "Blyth River"
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M. sp. Aru II
[attachment=909:name]
I tried to post more, but got an "invalid URL" message :s