gorby
Your question basically boils down to which are the best paints - I have no idea which ones you have tried. I suspect most of the amazing bare metal we see on here aren't acrylic paints, Alcad II produces some great finishes but I hate using it due to the smell. Sticking with acrylic, I've seen some excellent builds painted with Vallejo acrylic Metal Color – although not used it myself. Have a look at this:
davecoleysemporium.c..Colours-How-to-.html
Incidentally, many people spray metal finishes over a black base coat as they think it intensifies the metal sheen.

bughunter
Acrylics itself has nothing to do with the solvent (and so with smell), also all the new solvent based paints like Mr. Paint, Tamiya Lacquer LQ series, Gunze Acrysion, AK Real colors and more are acrylics, but solvent based instead of water based. The handling is much more forgiving and results are so much better, so many paint manufacturers move in that direction or at least offer a paint series additionally - they cannot ignore this trend.
Because of the handling quality and the results I love Alclad metal paints, but also AK Extreme metal are not bad (also solvent based). I started airbrushing at all with Alclad paints and was surprised how easy it was to get great results (my 1:16 aircraft engine project).
The smell is not a problem if you were a mask with filters and use an airbrush cabinet with exhaust. At least a mask is anyway recommended also with water based acrylics. The fact that they do not smell does not mean that the pigments in the lungs are healthy. And there are always pigments in the air because they are atomized so finely by the airbrush.

Nick Dragone
Thank you. My latest build and album is a 1:72 P-51 done with Vallejo aluminum over a semi gloss black base. I'm pleased with the results and ease of cleanup. I over sprayed it with gloss for ease of handling and to level out the decals.

Augie
So there is an alternative that you could give a try. Its what I use on mine and I've had pretty decent results.

Its Wax Gilt, amazon.co.uk/Treasur..ng-Wax/dp/B00HVUTMH4

Its expensive, but goes so far its not that bad.

These were done with it

Opps | Album by Augie (1:32)
In Progress | Album by Augie (1:48)
Building the Javelin | Album by Augie (1:48)
Fishbed 3 | Album by Augie (1:48)
F-86D Royal Danish Airforce | Project by Augie (1:48)
Build | Album by Augie (1:48)

Apply direct to the plastic with a soft brush and after about 15 mins, lightly buff it.

bughunter
As Augie mentioned wax: there are also some wax metal tones available as "AK True Metal" e.g. steel, alu, dark alu, silver, gun metal, copper, ....
I own dark alu, but not much experience yet (only used on a little part).

Nick Dragone
Thanks Augie, I can get this on Amazon but here in the US a similar product is called RubNBuff

Augie
From what I remember, a few other members tried rub and buff and the results were different, I've not tried it myself.