Use a three piece setup, two satelite speakers and a sub. Your cheapest/best alternative are consumer grade computer music setups. They have the amps built in, and they start around $50 for something small. You can go up to $150 and get something really good for that application. Even two computer speakers without a sub would be fine, but the sub is necessary to replicate the full frequency of the module. You should put the sub near the throne or next to the kick drum. Then you can set the satelites on stands, or even on the floor aiming straight up into the air, on either side of the throne.
I find keyboard amps to be midrangey and compressed for V-drums, and the Roland "drum amps" aren't much better.