Hi
Yes to confirm i run three zen engines, a 260pum, a 290pum and a 31cc mill pond tuned zen which is very quick. The zen 7 by pmc which my brother runs is also very quick.
All three have proved easy starting, relaible running and powerful with no breakages. I have been running one of the engines for three seasons on original bearings. The walbro carbs are bomb proof as usual, but go for the big bore carbs with no choke butterfly for extra power. Also a pmc pipe is a must which ever engine you pick for maximum power.
The new zens have the ez starter which is a lot easier on the knuckles and makes the pull start a lot easier to use without stressing the starter cord which can be prone to break on some engines. I do upgrade my pull starts by replacing the stock cord with dynema cord (which is stronger than steel and unbreakable) as there is nothing worse than breaking a pull start at the lake before you even get the boat running.
Cant fault the zens. I also run a stock sikk 26cc which has proved very reliable and powerful, plus quiet and high reving. ( it is a lot harder to start though due to compression)!
Cant commemt on the rcmk engine a have never owned one but i am told they are good.
Best regards
Garry dickson