Go with the Davis fuel, do not forget you get about twice the run time per tank on diesel so actual cost based on this less than glow fuel
ALso the LA series although a plain bushing engine it is very easy to set up ans usally bought as a first engine not a barnburner on glow
but keeps on ticking. The real surprise comes with the Davis Diesel head gobs power, one of the best conversions for not a lot of
bucks martin