Never ceases to amaze me when people spend thousands of $$ to get a D/F in the air and skimp on the most critical component.

JMHO, but if you're using a Viojet or a Viofan why in God's name don't you just get an engine from BVM as well? These components are designed to work together, while all the other combinations you're considering are not. They are compromises.

Don't compromise.