M&P Mercury in Burnaby and Bridgeview in Delta will both tell you that Optimaxes are wicked.
As for the Evinrude E-Tecs...let's wait and see after 2 to 3 years of HARD use what happens.
Actually...I had a boat with a 150 Merc, not an XR6....and there was an acquaintances boat--same boat...with a 150 Yamaha...I put the boots to him...I could run away and HIDE.
He took his boat to 2 mechanics...propped with the same 21 pitch...still..I had him by 1 mph or better.
I've blown a 150 Yamaha after 600 hours...yet I had a 150 Merc I used to run on a guide boat of mine with 3 seasons on it, probably better than 2000 hours on it...and I'd still run it flat out for about 30 seconds each day to blow it out..and I never blew a powerhead...the lodge mechanic said that Cop and CG RHI's had 4000 on them before they replaced 'em. WOW!
However, Yamaha or Mercs...both GREAT motors...still in the dark about Evinrudes though...esp. the E-Tec.