Just to follow up, it appears that this year graduates are eligible for the Allen and Overy Vacation Scheme.
From my previous experience as a graduate applying, I think it depends on your preference and personal strengths. If you were not sure you have a solid amount of legal and commercial experience to really explain why you should gain a training contract (That was my personal challenge), then I would say go for VS. It is great experience regardless and although tough can be rewarding.
If you feel like you want to prioritise getting TC offer, go for the direct route but just ensure that it is a strong application, and you've had some contact with the firm via open days or events. Hope this helps and best of luck!