My poor old boat had an engine failure on Sunday, an ominous knocking noise coming from the E-Tec. I made the call to head for home. The knocking suddenly stopped but we kept on going to get off the banks and into the channel as there was an out going tide. About 4km from the boat ramp the engine died with a loud clattering noise.

I have a Mercury 115HP on my 5.6m aluminium boat (purchased together 2.5 years ago). Mercury is not a Command Thrust model. No complaints at all. It's been smooth and reliable. Fuel efficiency is 2.-2.4 km/L on the plane at around 40km/h. No issues getting it on the plane, but it does take a moment longer if the boat is heavily laden.  

Smudge, mate has the Mercury CT on his 6.1 Surtees and hes pretty happy with it

pompey wrote: I have bought new a Yamaha 150 and Mercury 150 on different boats.  Liked the Mercury much more. Did about 100 hrs on each motor. After 10hrs the Yamaha tilt switch stopped working on the remote but still worked off the motor,  Answer to this issue, my fault because I must have been operating the remotes with wet hands and salt water has entered the mechanism, quite common I was told. Would supply part under warranty but installation my cost, est $1000. After a brief discussion they agreed to fix it. Went well after that. Mercury was quieter and used less fuel on similar sized boats. Mercury was cheaper as well and has a longer warranty.

Glad I have a merc/mariner.Throttle/ tilt gets spray on it all the time..

pompey wrote: After 10hrs the Yamaha tilt switch stopped working on the remote but still worked off the motor,  Answer to this issue, my fault because I must have been operating the remotes with wet hands and salt water has entered the mechanism, quite common I was told. Would supply part under warranty but installation my cost, est $1000. After a brief discussion they agreed to fix it. Went well after that. .

Etec,s are great when they are running. I had a 150 on my Marco 650 and it eventually become too unreliable especially when bar crossings involved. I replaced it with a Honda 150 and it was slow on takeoff, in fact I struggled to get it on the plane when 5 people onboard. I ended up switching to a smaller prop (smaller than the Etec had) and that helped quite a bit. The Honda or any of the 4 strokes will never compete with a 2 stroke on hole shot.

Hi Smudge , Get the Mercury 115 , I wouldn't bother with the Command Thrust as more for big loads , barges or those weird American pontoon boats. If you can find one,  get the XS version , good for 125hp apparently , still rated 115. I've had that motor on my 5.6m Marlborough ( heavy fibreglass boat ) for 7 years now and it is a beast . Super reliable , starts first time every time which is very important for the west coast. I've done plenty of Manukau bar crossings with it . I did lots of research before buying it,  and what I liked the most was the simplicity , ie . less moving parts than the multi valve Suzuki's and Yamahas , but bigger cylinder size , resulting in the lightest motor in its class , the most torque , most fuel efficient and the least maintenance so lowest servicing costs . They call it lazy horse power , so less to go wrong. To top it all off , they have been designed for anyone to do their own servicing , which I'll probably do after retiring. I'm averaging 10L an hour for all motoring which is mainly doing between 3000rpm for 16knots just on the plane if lumpy or 4000rpm for 24kn , with the odd burst of 5800rpm doing 38kn. . Cheers

My top secret excel spreadsheet says you'll need twin 300s to fit my arbitrary "well powered" definition. It's like your Mrs car driving up a hill with a boot load of shopping. Or something like that anyway, I forget. Where's a guru when you need one?

That's just a slogan and quite likely incorrect . The fewer moving parts an engine has the more reliable it will probably be. 

The Merc 75 , 90 and 115 are all the same block . Why would the 115 put you off ?  These new generation Merc motors have been out about 8 years and way better than the past . Most owners rate them , I certainly do