If you really want to buy new, the Spark would be a good choice (being the newest, it should have potentially better resale value). Ozone wings are superb to fly and designed perfectly for each market sector.
In real terms however you would not notice any tangible difference between a Spark and a Nemo power, or even a slightly older model like the Ozone Indy or (many other types). Any beginner wing will be safe and easy to learn on, but slightly slower than the intermediate or advanced wings (providing you stay in the certified weight range). You will enjoy the flying just as much on any .... then worry about the actual wing when you have gained experience in various conditions, used the full trimmer and speed bar system etc.
The price of new wings has gone ridiculous. My advice would be to buy good used kit (there is plenty about, but get advice first - on here or from an experienced pilot / instructor you trust). There have been quite a few Nemo's and similar for sale recently. This way you won't lose much money (if and when) you eventually think about getting an intermediate wing.
I refuse to engage in a battle of wits with any unarmed person !! Custom Kobra Frame with Polini 200 ES Dudek Hadron