tbh i know you want a valver, but it would be better to buy a 1.2/1.4 and have and have that a few years, get driving skills, that way your insuence will be cheaper and you will appreciate the valver more when you get it.
Not saying you are a bad driver, but at 17 you lack the driving experience to handle the car at higher speeds, and the judgement to know when it is appropriate to go faster.
Trust me i know, been driving for a year now, in all honesty my driving could still improve, and as much as id like to have a fast car i still feel that i dont have the driving experience to full control it and to fully enjoy it. After all you dont want o buy a nice valver, and then 2 months down the line put it into a ditch after a night out, cus trust me, tiredness on its own presents problems. When you are an inexperienced driver it is very hard to judge braking distances in the wee small hours when uve been dancing all night, its dark, u have ur m8s pissed and egging you on, and you are tired. Fortunatly i have had no crashes, but i have a had a few near misses, that only my quick reactions have been able to prevent.
This is just my personal opinion.
if you are insistant on getting a valver try gettign it in ur parents name, im wiht CIS, they have reps that come around and deal wiht you personally, my rep insures my whole family, even tho i have my insurence in my mums name, he knows that i havent had any crashes, and he treats my insurence liek my own, so i am building up my no claims bonus, as well as my mum, and technically she has two insurence policies in her name.