Problems with btc:
1. wild, unstable exchange rate
2. difficulty to obtain and use (for most people)
3. getting coins hacked or lost by sending to wrong address
4. fraud/theft at exchanges (if it happened at Gox it could happen anywhere)
5. it enables criminals to get paid online
6. there are already plenty of ways to send money online a lot easier, it doesnt really do anything new
7. absolutely no buyer protection
8. scam companies/scammers
1. This is just a functional of the relatively small market cap and speculation in BTC; as the market matures this will be a self-solving problem. But it's a bit silly to complain about a "problem" that exists only because BTC has rocketed upward in value in the past 5-6 years. That's like complaining Apple stock has a problem because it's been so profitable.
2. It's easy to sign up on coinbase and link your bank and/or credit card to it, to buy BTC. Trivial really, and no harder than signing up for a new user account on any given retail website. So I don't buy this one either.
3. I don't see anything unique in this - in principle you can make equivalent errors with Fiat transactions.
4. I agree this is a problem; customers of exchanges do need to keep voting with their funds, favoring exchanges that are the most transparent and aggressive in maintaining good security. Fiat exchanges in principle could be just as vulnerable to online theft, so I see the difference here as largely one of crypto exchanges being less well-funded and they've not been around long enough or have enough experienced employees to have a full security system in place.
5. Criminals also move fiat around on-line. Granted, the pseudo-anonymity of crypto is attractive to criminals. But it is also attractive to legitimate dissidents to repressive governments, and free citizens worldwide who shouldn't have government/neighbors/anyone else snooping on them either.
6. With logic like that we'd still be walking and refusing to ride horses, much less drive cars! Sure you can send fiat around with a 2.9% or $10 or more transfer fee, but BTC is MUCH more efficient. And much faster. These are clear wins for crypto that will ultimately force the issue -
people do not like wasting money and BTC/altcoin transfer efficiency will steadily defeat competition over the long haul for this reason.
7. Buyer protection is only as good as the company offering it anyway; legitimate businesses will treat customers fairly if they want to avoid a death spiral of negative publicity. I think this is the one issue BTC supporters stress about more than they should. It's not a non-issue, but long-term business self-interest makes it much less of an issue than many people think.
8. Granted there is an intense focus by criminals on bitcoin these days; most of us here for any length of time have shrapnel in us attesting to that fact, myself included. So I'm in agreement on this one, and think we as a community need to develop and publicize best practices for individuals and businesses to defeat the scammers. If we can block 90% of the scamming with a reasonable combination of security improvements at exchanges and so forth, and increased user awareness, and improvements in wallet software and so forth, we'll hopefully drive the scammers to go chase lower hanging fruit somewhere else or just give up.