I didn't buy Terrahash, but here's the outcome if I had:
Hashrate delivered

Company	Hashrate delivered and running
BFL	540GH/s
Terrahash	0GH/s

So, it comes down to what "reliable" means.  LOTS of BFL customers are hashing with their hardware, and ZERO Terrahash customers are hashing with their hardware.  Sure, BFL was super-late, possibly lied through the process, produced a few duds (I have a slow one myself), produced and shipped units REALLY slowly, but in the end, they did deliver, and I'd say that's more reliable in the end than a company that goes under and can't even fully refund everyone.  Of course, you're right that there's just more BFL customers, so maybe proportionally Terrahash customers are more upset about Terrahash than BFL.  All of my BFL hardware has more than ROI'ed in USD (yeah yeah I know it will never ROI in BTC opportunity cost).

Of course, you could say Terrahash's statements were more reliable than BFLs - I agree there.  It's just that one of those statements was "we're done and you don't get your money back."  That is a pretty reliable statement.