[tferris]

None of them will bring substantial traffic, users or virality (but HN brings you slightly more, if you are doing good ~20-30K visits while TC hits you ~5-10K).

If you are raising money or raised already and prepare the next round being on TC is a must. Not only once, better several times. Consider also Mashable, maybe not the same brand but you will get much more traffic and virality than with TC.

Regarding hiring devs HN is of course better.

To get on HN on the front page is much easier than with TC.