Homemade Coils For GPX?

just wondering if any of you have rolled your own GPX4500 coil and had success finding gold?

Also, did you notice anything your coil did better compared to similar mass produced coils of the same size please?

I'm in the middle of final tuning my first home brew coil and was wondering if I'd benefit being + or - from 300uH

Thanks

https://www.prospectingaustralia.com/forum/doc/member-docs/4485/1600580091_fastcoil-1.pdf
I've never made my own coil & probably won't ever bother to. Would need a lot of spare time, equipment & patience of which I'm low on all. I'd prefer to be swinging a coil than winding one.
Have dabbled in DIY batteries, audio etc. so it is still interesting to me though & would be good to see more working DIY coils etc. on here. Doesn't seem to be a great deal of people doing it much on this forum?
Inductance of ~300uH seems to be the industry accepted standard for fast pulse delay coils (<30us).
Have read that a higher inductance can increase target signal but then also increases ground noise, EMI etc. so around the 300uH is probably the happy medium found by years of industry trial & error?
Other things like resistance also seem to be key especially with Minelab detectors?
Maybe join Geotech & get some feedback/advice there? A lot of their discussions are way over my head but some good info on there for those who like to dabble in detector DIY.
https://www.geotech1.com/forums/forum.php