That depends on what you want, but mostly altcoins mining are not like Bitcoin mining, so you don't really have to mention the hot hardware lol. But from my previous research, mining a new coin is better than rushing in and buying it and speculating that the price will go up. Most people that have tried it really got some good positive results from mining altcoins than buying. Unless you're talking about Bitcoin, then I would say that it is better to buy it, cause the price can move up a big way at anytime and you will make profit (there's still the risk of losing though.
Yeap I forgrot to mention that I talk about GPU-mining. It's more flexible than Bitcoin mining because of more oportunities to choose a coin. But to find new coin in "stealth" mode is also very hard task. I try to check message boards about new coins but currently I use nicehash for my GPU rig (I don't use algo switch soft I configure my rig to nicehash stratum). Maybe at the end of this week I will convert my "test mined" BTC to altcoins. Also my "Buying" portfolio probably will be changed too