I like them both as names, but sadly they have connotations... an obnoxious kid from church, and an obnoxious classmate from my youth, respectively. :p Doesn't help!
I actually really like "Calvin", partly from A Wrinkle in Time, plus just the combination of sounds... but we happen to be Calvinists, so it would probably come off as kind of fangirlish or something. My inlaws would definitely not be impressed!
I'm a Sarah, and having such a popular name did annoy me - I was always Sarah M in class, along with Sarah J and Sarah T and Sarah C, you know? Then again, we do plan to homeschool, so if we had a Liam he would be the only one in his class... so maybe it wouldn't be such an issue? I don' know! I'm not so keen on William, just because I don't like Will or Willie as nicknames (and my family has found through bitter experience that controlling a nickname is easier said than done!).
I quite like Hunter too - it's a family name (well, surname), but that's also trendyish at the moment; and DH is unsure, anyway. It certainly doesn't help that he vetoes 99% of the names I like, and has suggested precisely one boy's name - Alejandro - which seems unsuitable to me for a kid with next to no Spanish blood in him! (And doesn't really match with Rowan, if you ask me.) The fact that we AGREE on Liam is definitely a point in its favour! And yet, and yet... arrgh.