I never used that wallet and nor have read something about it, so I don't know what to say.
If you are selling and you want to put a part of the profits in BTC apart (as a future investment), it's better to tumbl that BTC and store them safely inside an offline wallet.
A short explanation (taken from the internet) about BTC tumbling:
When you tumble cryptocurrencies, you essentially take bitcoin from several different wallets, combine them, redistribute them into different wallets and then do it again. Essentially, tumblers take a set of bitcoins and return another set of the same value (minus a processing fee) with different addresses and transaction histories, thus effectively “laundering” the coins. Tumbled cryptocurrencies lose many of the attributes that make untumbled cryptocurrencies traceable. As a result, tumbling works a lot like TOR itself: It doesn’t really anonymize the transaction; it just makes it more difficult to trace because it washes it through multiple transactions. Even tumbled transactions can be “untumbled” if you have the time, the patience, the data and the processing power. Services that operate legally must keep detailed records of how the coins were mixed, which could later be hacked or subpoenaed. The more mixing you do, the less likely that your mixing could be reverse-engineered.