Dicho says: "Initial G with u in many Spanish words is pronounced Hua, rather hard, almost like the J in Juan..." I'd been taught in school that the Spanish "gu" is pronounced like "gw" is in English but with a less hard "guh" sound... so I guess it's somewhere between a "gw" and a "hw". But "Juan" would have slightly more of an "hw" sound than "Guan-" would, again according to what I was taught. I'm sure the pronunciation varies somewhat with different dialects; even in the US, I'm sure the Latino population of the Philadelphia PA area, for instance, have a slightly different "accent" than Dicho would have heard in Texas. Also, I've been told that Cubans pronounce their "h" sound very hard, though I've never heard it personally.