Hey mate 

as you know I have the same set up my suzuki 140 just but lacks top end speed - I would go the 150 suzki. Having said that I know someone who has the 140 suzki on the back of their Bonito and he does 40 knots. It may be that I have beefed my Baron that or it is just the hull design.

hope that helps.

 Can't comment on the Honda but recently sold a cuddy cab with solid hull weighing about 850 kg with a Suzi 140hp 4 stroke on back and was extremely happy with it. If it is speed you're after I found a 21 pitch prop pushed it along at good speed,economy and quiet. I also had a 19 pitch prop that was better suited to when loaded up with people or gear. Maybe even need a 17 pitch if looking more for power rather than speed but the dealer should point you in the right direction there depending on how you mostly use the boat.   I actually hit something with the prop which resulted in a bent prop and broken steering cable - mechanic said if it was a stainless prop then less give and probably damage to motor. As with most comparisons whether brand of motor or type of prop there are advantages and disadvantages and need to see what best suits you.

you may also want to compare weight of the motors as may be a factor for your hull, how far to local dealer etc

am sure you will be happy with either being new motors

135 awesome motor.   Has never let me down and great on fuel 

 I had a 90 Honda on a previous boat and it was great. I now have a Suzuki 175 and I realy like it! from memory I don't think my Honda supported NMEA where as the Suzuki does but that may be different nowadays...

I don't think there is many Honda dealers/ service centres in perth anymore so that may be an issue and as boora mentioned the weight difference- I think the Honda is heavier..

 I had a 115 yamaha on my baron.great motor but a 150 yamaha would be a good motor i recon for it

Although this guy was questioning the 135 merc.  Guess id be checking if the Honda is a 3l or 2.

"I've got a 2014 140 Suzi and love it, but from the specs, the 135 Merc would be a torquier motor. It's 3l vs Suzi 2L. Dealer support being closer, and price similar, I would go the Merc without hesitation "

" The 140 Suzukis are excellent. However they are a higher output 115 and their displacement reflects this. Much like the new Yamaha 130 is a higher output 115 and the Etec 130 is a higher output 115. Then you have this new breed of 150 class engines bought down to a midrange sticker, like the 135HO Etec being a detuned 150 and the 135 Mercury being a detuned 150. Forget the horsepower number on the cowling, what you are getting is the torque delivery of a 150 class outboard, that's what these engines are all about. No contest, go the 135 Mercury. The dealer being closer is icing on the cake."

 Thanks for the help you blokes

Since I do most of my fishing down south in larger seas, speed is not the aim. I want grunt, fuel economy and best for my dollar.

Im thinking the 7 year warranty with the Honda is a big deal, also the larger displacement (extra 310cc), the BOOST technology for hole shot power along with the dual stage induction for top end torque. Im leaaning in towards the heavier stainless Honda, have heard that the alloy used in Suzuki engines will cause problems down the track with internal corrosion.

Thanks again. I will be uploading some pics down the track of my progress on the Baron.

 Agreed the hondas are very good.heavy but good

I love my 135 Honda, has 380 hrs on the ecu and it is very quiet and economical. It's on the back of a old Mustang 2000 Tournament and I can squeeze just on 40 mph at just under 6k with a Permatrim Hydrofoil and Seastar Hydraulics fitted. 

My unit is 2007 and NMEA is only on models from 2010 however I have no real need for it so it's not missed.

FWIW on thehulltruth.com its well regarded that the 140 zuk is alot les then the 140 its stamped with apparently around the 125-127 mark.