Hey Luke, Good to hear another rider getting into trials.
Like people have said decide a size first but if choosing mod one thing i would say is dont get the onza pro. It was my first bike when i first started, and i literally had to tamper with it like every half hour when out riding and also constantly i had to buy parts to upgrade. Like i ended up with just the bars and frame. I changed both brakes completley, both wheels (not cheap), pedals, and before i got a new bike i was about to change bottom bracket and cranks.
I would just say its not worth it. Its a good starter bike for riding but rather expensive to maintain, seeing as your on a tight budget like me.
Hope this helped, and hope the other riders can give you a hint towards which bike.
Good luck!