Is it safe to buy an EU unmerged account?

[Retrosix]

Recently I've been thinking to buy an EU unmerged account only for the achievements, mounts, pets that may be inside.
I'm planning to log on it only 1 time to activate the achievements, mounts, pets, meaning I'm not planning to bot on it nor play on it.

Is there any risk involved as long as I don't play it?
Has anyone experienced any ban yet?

[esp3rae]

No risk for your account if you do this for the achievements or mounts. Blizzard can ask you one ID card or gaming licences after a lock of your unmerged account, but your main account will stay safe. Never saw one EU locked unmerged account.

[Cecu]

On EU, blizzard usually lock the unmerged after reports and manual investigation, which lead to 72h suspension on it, from gathering etc. But I havent seen any locks, simply because its unmerged, w/o other offence.

[gippy]

Bought around 6 looking for achievements, had one locked because i traded sold gold off it as there was nothing special on it and that's it. The rest are still alive and kicking.