"Why make a 20V go fast?"  "Get a speed hull if you want to go fast"
Why not?   It is a lot of fun on the relatively cheap.  It is a great hull, loaded with space and handles well with the extra speed.   Speed hulls are generally designed for one purpose and I have yet to see a 20' center console go fast that is a good fishing machine.  I want to keep a livewell full of pogies or threadfin alive at 60 while I run to my favorite snook hole, in the shade of the t-top, while enjoying the radio and be able to stop and grill somethin good for my 4 passengers for under $20K.  
 If my 250 Merc wasn't reliable I wouldn't own it.  
The car motor is more reliable than the outboard in most cases.   Seaworthy and reliable is very important, I couldn't agree more. 
Granted, top end speed is not useable in some conditions.  That will be the case if your V tops out at 35 or 70.   The captain has the tiller and the go stick, the ultimate decision, when and where to use the POWER.. is up to the driver.  
I congratulate UBHSTRY for a great build, testing and thanks for sharing.  I am personally out of coin to chase any more MPH, thanks BGREEN