The Gold Bug Pro is not exactly but somewhat like my Xterra 705 Gold w/ 6" DD HF coil at 18.75kHz and will detect larger gold down deeper than the Gold bug 2 and is great for other coin, relic hunting etc....but that Gold Bug 2 with the 6.5" coil screams on very small flakes of gold up near the surface where my 705 barely hears it at the surface 2".....The Gold Bug 2 is still very much in production today and cost about $100 more than the Gold Bug Pro which is a very very good machine..... you just need to decide what type of detecting you want to do.
Joe