Spark Trooper vs. Firemane Avenger

[DU7CH13]

So I've been building and tweaking this Boros deck, and I'm just wondering what are some people's thoughts on Spark Trooper vs. Firemane Avenger.
I really only want one of them as a Boros 4-drop and their value has shown through for me on both counts.
I guess I'm just more interested in other perspectives right now.

[Monrodesign]

Spark Trooper + Silverblade Paladin

[DU7CH13]

That's a wicked combination

[Bookmeister]

In a good Boros deck the trooper is more effective. You should win before the Avenger can be very effective. I went with Sparky.