I would split my funds, as bitcoin seems to be more stable and altcoins are cheeper now, but there are many doubts as for their reliability
Splitting your funds and investing in more than coin will be very much difficult thing and it will not be easily managed. You need to go for investing in either of these based on your own planning and strategy. For me, investing in bitcoin is far more beneficial than any other thing may it be investing in altcoin or ETH. But it is you who has to plan and decide accordingly.