In order my my preference based on capability out of the box be it kit or complete saw:
"Blue" g660. far and away the best bang per buck and they have and will continue to improve them. Guess in a few months improved cranks and oil pumps are in their future but they work pretty well right now. For most a way better deal than buying a built kit or even building a kit. Time is money, and you are either spending it or paying someone else to assemble these...can't beat the "blue" options....period.
TENTATIVE number 2, a g5800. While NOT a power house, it runs and operates pretty well. A 60cc saw that runs like a clean 50....but has potential and is only $110 bucks delivered
three: g372 over the other two offerings ( xt & xp) if its being used as delivered, conversely if you plan to build and or modify a g372xt variant....a video in process to explain.
For 75 percent of folks interested in this stuff, I would start with any of the above before buying a kit, and modify from there by adding better top end and carb option, or even if you want to port one of these..
After that I guess the three kits that have worked out well in order of preference to me:
1) 660
2) 365/372
3) 038
Everything else was workable but the "pita" factor was more than was worth my time. Mainly because the standard set by first two, 660 & 372 can be built into anything you want.