Excal 1000, Excal II, Sovereign GT, CZ-20, Tiger Shark, Tejon, GTI 1500, Surfmaster Pulse, CZ6a, DFX, AT PRO, Fisher 1235, Surf PI Pro, 1280-X, many more because I enjoy learning them. New Garrett Ca
Changing coils to these extra large things won't improve finds much unless you are looking for relics that might be deep. Your find ratio actually improves with a smaller sniper coil because you get the beep and save lots of time recovering it instead of having to kneel to dig. Won't matter much which program you use.
I would have to disagree, I use the 15x18 SEF coil on my V3i with great results it even works well in moderately trashy areas, I wouldn't say it is getting better depth on coin sized objects but it doesn't miss clad at a solid 6-8"s oh and pinpointing is amazingly accurate!! I use it most of the time and I always come out better than my hunting buddies.