Mechanical keyboards may have lots of travel, but you don't have to use it all. While a mechanical keyboard may have 4-6mm of travel and scissor switch keyboards (like Apple's) only have 2mm, on a mechanical keyboard you don't have to bottom out the keys. Topre switches activate around 2mm - the same as your Apple keyboard. The difference being that your fingers aren't slamming into a hard plastic stop after each activation (unless you choose to bottom out your keys). Furthermore, well made domes don't tend to wiggle much more than the keys on an Apple.

I'm not quite sure what you mean by big gaps - Apple's keyboard also has some pretty sizable gaps between keys. Unless you have tiny fingers I think you'd want those gaps.

More information here: http://geekhack.org/showwiki.php?title=START+HERE+--+The+Gee...