I am not using any other crypto currency at the moment, but I don't think any of them will ever overtake bitcoin. Its the standard of all, its like money now, do you see money competing with anything else? I really don't see that. So I feel bitcoin will hold it own in the market and would probably keep growing.
Yes I think so ,because presently its unbeatable though its volatile in nature its still stand its ground and stay at the top. Bitcoin add value more than other coins although altcoin are there, they are just subordinates.