Sandslash, Just because they're awesome.

I'd have to agree. Sandslash is far superior

Agreed.

Thirded, but then, Im biased :P

I know how hard this is. ;3;

there are several ways to do this like pros and cons, physical look similarities, but to do these you need to do research. itll be a big mistake to let others choose who you are. try sketching out the pokemon doing their moves or read up on them on bulbapedia or serebii.net. the more you know the easier it will be to decide. oh and don't forget, pokemon have natures and characteristics so no two are the same. don't be afraid to be different, itll make you shine.

it still comes to me not knowing which to use. lol

Sandslash for sure.
Course, given I am one (Well half slash, half dragonite) sort of makes me quite biased towards one. Still they're quite awesome, so slash is my vote.