My sister has one too and it's a great handling little car and it's economical too. It's a little slow but after you've passed your test that's a good thing
I wouldn't buy a modified one myself because they are the type of car that new/young drivers are buying and they are often hammered to death, I'd buy a standard one and modify it.
Things to look out for are the electrics on the doors. The wires can get broken which means that the central locking can pack up and the electric windows.
There are plenty of upgrades out there for them

My sister has a set of gti 6 cyclones for hers that I've refurbished in white, s16 front struts, springs, hubs, disks & calipers and an induction kit all to go on
Go for it, I think you'd like it

She's on her 2nd and she loves it to bits.