is it still worth to buy monero?
I buy a small amount every week no matter where the price is and haven't regretted it yet. Only wish I had been doing it sooner (as in before alphabay).

The next Alphabay will have a much, much larger impact on the fundamental value of XMR. For one thing, it won't allow BTC or ZEC (insert image of Cazes hanging by his belt in a Bankok jail cell). For another, it will grow faster and to a much larger size:. The pent-up demand will be enormous, and the fear factor involved in using BTC or ZEC won't be there to inhibit transactions.
But bootstrapping trust requires magic. How long that will take, I do not know. If it takes too long, a technical solution will emerge.
Cazes was caught by using a hotmail.com address in the AlphaBay welcome email, which had nothing to do with BTC. Are there any known cases of darknet market users being caught by tracing BTC transactions? I doubt police in most countries would have the resources to do that.
And even if they use Monero, they would still leave a trace on their exchange when they cash out to fiat. So I don't see how using XMR on the DMNs makes much of a difference.Edit: I thought about this some more and I see the benefit now. Monero is untraceable and as a vendor this has great utility. Although I expect governments to hate this. Bitcoin will be regulated. XMR will be outright banned.
One question: Assuming future darknet markets adopt XMR, will the Monero network be able to scale to accommodate that?