I have a customer who wants a black, red and silver cake with buttercream. I know some buttercreams can be difficult to get bright colours.

Which takes colour better ABC or SMBC? 

I don't have and can't afford an airbrush. Maybe I could buy some of the colour sprays? Has anybody used these?

Any thoughts would be helpful.

Thanks

The sprays are great for the first third of the can, then they start to clog up and drop huge droplets which look awful.  

Buy readymade black buttercream - CK brand is one I have used before - (but you may want to warn the customer of the green #2s to follow).  In fact, I'd probably buy ready - made black and red.  

SMBC if using butter will never achieve those colours accurately, so definately spray or buy ready made. 

I use the Wilton whipped buttercream and it colors well. But I use the Americolor super black and super red. I have also used the spray cans and they work well - just have to keep shaking them. The Duff ones are better than the Wilton- only Duff makes silver here - I used 2 cans for a big area or if I want it really solid. But it really depends on how big a surface you need and what type of look you are going for,,, 

I have used the Wilton blue for water/waves and it worked great or green for background. ...

Thank you both. I will talk to my customer and she what she prefers

FWIW, when I need black buttercream, unless there's a compelling reason not to do so, I first make it into dark chocolate icing (by just adding cocoa to some of my buttercream until I get a color i like, thinnning with water as needed), and then add super black food color.  Minus that last step, it's also how I make brown icing, starting with cocoa, then adding a bit of golden yellow to warm the color or black to darken it as needed.

Obviously you need to make sure the client doesn't mind having some chocolate icing on the cake.

If I only need a small amount, I just buy a tube of black icing and use that (thinning it a bit if needed).