Agree. Bitcoin is the best crypto for investment, moreover for long term investment / holdig. We have known the value of Bitcoin, the trust, and also the worth of BTC itself.
BTC may always face some difficulties because of FUD, but so far, it will be able to recover again. Although right now, the price of Bitcoin is still very volatile, more to drop more ignificant. But, it doesn't mean to decrease the value. We can still keep holding while waiting for the next bullish era.

For altcoin itself, some are worthy, but mostly they are shit coins. So, becareful when going to invest in altcoins.