If you take "Grubee" out of the above and add in "all Chinese engine kits" and I'm in about 100% agreement lol - the oversized downtube
is an important consideration tho
ALL of these kits have pisspoor castings, particularly around the cylinder's intake, exhaust, & transfer ports - the cylinder's mutant fins are an obvious, external example of this. While easy 'nuff to fix w/a lil Dremel time - it's the pitting and flash in the ports that's pretty much the main cause of a lack of "out of the box power" and no brand is any better than another - it's almost purely random chance. Why just the cylinder castings seem so much worse than the rest of the engine - regardless of brand I just don't know lol
While I personally favor Grubees - it's only for very minor things like the extras included with the kit and not really 'nuff of a reason to like 'em more than another. What's far,
far more important than lil things like your choice of motor mount bracket (alloy or steel), longer clutch cable, or the "new improved" carb (which is just a lil less junky than the old one lol) - is that you get w/e engine kit from a reputable dealer with a track record of exemplary customer service.
What vendor you get yer motor from is
so much more important than the marginal differences between brands - most of which are a moot point anyways if you plan on actually fixing up/modding/and otherwise improving on the basic kit anyway *shrug*