I'm very surprised - everyone is mentioning classical sword styles, I may have missed it, but I didnt see anyone mention a single modern sword or sword maker like Steve Ryan, Jerry Hossom, David Winch, Mineral Mountain Hatchet Works, Barry Dawson, or even Wally Hayes.
Okay, yes, some of those guys use classical patterns, but they update them to work for today.
Personally I'd go with one from either Jerry Hossom, or Laci Szabo.
I think Jerry has forgotten more about balance, edge geometry, and steel qualities as it pertains to modern swords than any of us are going to hope to know. He makes some really nice pieces, that can be had just about anyway you desire them and would be right at home on the modern battlefield. Check him out,
www.hossom.com and
www.BladeArt.com also carries a lot of his stuff.
Szabo doesnt make his own stuff, he designs it and has custom makers make it - and he makes some really nice pieces, radical but nice, serious, fighting cutlery. His Modern Gladius is a really nice looking piece,b ut I would probably go with the All American (Not the All American II), as it is a simpler shape, very straightforward and would be easy to handle, for utility and killing. (Its a sword - dont mince words.)
His site is
www.szaboinc.com
Modern steels, modern materials, modern ideas of close quarter warfare, modern design concepts. Modern swords all the way - please.