While there are a whole bunch of drum synthesizers on the market and many of them are very competent - my selection ended up with Audio Damage Tattoo, Audiorealism ADM and Sonic Charge Microtonic. My primary criteria was that they should be available for both PC and Mac - and they should be able to create more than one type of overall sound. I chose not to include any of the drum machines from the polish developer D16, as each and every drum machine is locked to a specific model and besides - I don't own licenses for any of them.
Waldorf Attack is a classic that I seriously considered to include, but decided against as it doesn't contain a sequencer. Also, three products against each other is clear as a german sausage soup. But the Waldorf Attack is a fantastic drum synthesizer, especially for creating weird electronic percussion noises.