First thing's first: I am a passionate lover of FPSRTS genre, having played both Savage and Natural Selection (1&2) for many many hours. So bear that in mind.
So what's Nuclear Dawn? It is a representative of a very rare breed of video games, which combine classic FPS action as a foot soldier and Top Down RTS style commander role. Two teams fight for dominance over critical locations on the map with commanders providing support in form of abilities and buildings which allow forward psawning of reinforcements, ammo/hp regen and defences.
The game itself is fast paced, with several classes to choose from: classic Assault with powerful weaponry, able to take a few hits before going down and iconic thermal vision which negates invisibility, EXO with tons of health and deadly weapons, most effective against buildings, Stealth for general sneaking about, either with knives which can backstab unsuspecing players to sniper and unique sabateur with remote bombs, and lastly a trusty support with lightning-fast firing SMGs, shotgun or a freaking flame thrower. Everyone will find something fun to choose from.
Unofrtunately the game does not have a massive following but there is a good server or two, one in US one in Germany to choose from.
As always remember: there is no middle ground when it comes to FPSRTS matches. You either get a complete stomp of a match, which thankfully does not last too long or you get a very fun and amazing experience, which will keep you coming back for more, day after day.