The amount of people i know who have studied law (sometimes at top universities) aiming to come out of it being a lawyer or solicitor and have failed in that is.. well, all of them.
The chances you'll be a solicitor after your degree is very small, you'll probably get a menial job in a small law firm like most people do.
There are way too many law students and not enough jobs - also if youre not expecting to go to one of the top ranked unis, i would defo drop it, but that's me - i'm not so much driven by passion, more by the logistics of what will drive me the most success in the future.
But may the odds be in your favour if you do go ahead with it..