I run Alpha & Werks, both are great mills.
A Werks B5 with 2013/2058 will do the work without a problem, so will a Alpha S852/A852/A352, with a Alpha pipe, the nice thing about my Alpha is it has ran for 45 liters now, and still ripping.. I've never reached that with another engine.
Also Clockwork racing has very very nice mills, such a shame i don't live in the USA, otherwise i would run CRE(Clockwork Racing Engines) only..