Dash transactions have always confirmed in 15 minutes for me. It's simply the best service I've experienced. BTC is a relic. On the other hand most alt-coins are way better. My top 3 are Dash, NEM and PIVX. There is simply no reason for me to use BTC. All the merchants who accept BTC also accept Visa and Visa is instand (like Dash/PIVX) and at times even cheaper than BTC.
I doubt BTCGold would outdo BCH. People who own GPUs are mining Monero and other cryptonote coins.
I will definitely be testing my mining gear on BTG(name?). Controlled mining and higher payouts possible. As far as speed, nothing beats Verge that I know of....that is out already and functional anyway. I'm usually confirmed and moving currency within a couple minutes max. Occasionally a little longer, many times within seconds.
If you use InstantSend it's 1.3 seconds. It's what Dash claims. I haven't used a stopwatch. But the number seem accurate. It's simply instant. PIVX is pretty much a Dash ripoff (like LTC to BTC). So you should expect similar results from PIVX. I haven't used XVG.