That's what you write now.
Many people get the "kite bug" and go deep. Others don't. If you're sure it will remain casual then get a cheaper one, but if you feel more serious the cost difference is relatively small in the long run.
If it helps, consider hours of entertainment per dollar. Your first learning will cost some extra sail life and repair costs for broken spars, but they are good for many hundred hours of entertainment. The Vertigo and Rev EXP are made from a different fabric than the others which is heavier (Edit, see note) but it also can aid beginners by being slower and more sturdy. But after your first few flying days you may not want that.
Go fly other people's kites and learn what you prefer, then buy that. Fly other people's kites in a variety of conditions and wind speeds if possible. You should also try dual line, and other styles like speed kites, power or traction kites, which also have dual and quad line options. All are fun in different ways.
You originally wrote 3-20 mph range. While there are kites that can do that for a short time, for most of us that means three different kites. A full sail quad can handle the lighter winds but will be stretch out of shape quickly at 20 MPH with high risk of damage at every gust. A mid vent will struggle in light winds and be difficult at 20, but with experience could fly the full range. Neither endpoint would be particularly fun, though. A full vent would not fly for a beginner below about 10 MPH but would be strong at 20. Above 20 you would want a different sail, as well.
/Edit: Looks like the Vertigo's different fabric is somewhat lighter. Their web site says it's a slightly lighter polyester, rather than the more typical polycarbonate (PC) fabric. Either way, the EXP and Vertigo models use a different fabric than the ones used on most of the other major models. It's something to consider.