Recommendations for Most reliable/repeatable flame licker engine

[Petit]

Hi folks,
i have built the ridders internal valve flame licker engine, as most of you will know they are quite tempremental etc. Having looked at many videos of different types of flame licker engine there are many which appear to be alot more robust, easier to start, more responsive and have much quicker rpm than the internal valve model. I am looking to make another model but i would like to know what you would recommend?
Cheers
Joe