Hi - I have a 5hp Honda 4 stroke on my Pioneer tender - it usually starts on the first or second pull, sips the petrol - has a seperate 14 litre (I think) tank and over the last three years has been very reliable. The engine is perhaps a bit primative - have a look at similar sized Yamaha - they are very good too - perhaps even a bit quieter!
Cheers
Pelican
Tadpole, we had an 8hp long shaft 2 stroke Yamaha on the back of our Sadler 26 for 7 years. So long as you look after it i.e. correct mixture, clean fuel and a flush with fresh water, ours was brilliant. I estimate it ran at about 2 to 3 litres per hour in cruising mode i.e. 4.5 knots and probably double that at full steam - 6.25 knots I recall.
I have a Yamaha 3.5Hp that is 29 years old this year. It is even air cooled to boot.
starts second pull with out fail and has never been opened up. I can definatly recomend Yamaha.
Best of luck with your choice.