I have used a T2+ for gold prospecting. It will work if the gold nuggets in the area are big enough and not deep and the ground in the area isn't too mineralized.
The nugget small size limit for me was right around 0.2 grams with the T2+ if those nuggets were below the surface even an inch or so in mineralized ground. Any deeper and the ground mineralization just swallowed up the weaker target responses. That is the major drawback to using any single frequency VLF detector for any kind of detecting for smaller targets. The ground mineralization determines the effectiveness of these lower single frequency detectors. Will they get quiet and stable enough for you to hear smaller gold targets and deeper targets or will they be hard to ground balance and go off on just about every rock bigger than a small pea and make hearing weaker responses impossible to hear.
The T2+ did not work well at the gold prospecting areas I detected in the Rocky Mountains. Just way too much soil mineralization, large magnetite and hot rocks. The Teknetics G2+ was a little better. It has one of the quietest, stable thresholds that I have ever used.
Most of the guys and girls I know that are using VLFs for gold prospecting for detecting out here in the western USA are using simultaneous multi frequency VLFs like the Manticore, Equinox series, the new Goldmonster 2000, Nokta Legend series and Deus 2. They can handle the tougher ground conditions easily, have better depth, have much more sensitivity to even smaller gold nuggets than 0.4 grams, are waterproof for streams and creeks and have lots of features and settings to help with the dig/no dig decision so that digging it all even in the goldfields is no longer necessary.