I think the GDL is pretty standard and the ones that probide it are ones that also provide the LPC. LPC was originally only run by UoL as they were owned by the Law Society then I think they sold off to some venture capitalist? The only other provider at the Time was BPP, then some law schools started to run the LPC and GDL. thats why not every Uni does it.. the ccourse will be similar and not much snob value, so is just pick what location youd like. UoL is middle of the road if there was a rating it definitely wouldnt be the worst, but if there was a top then it wouldnt be there either imo.
If yu do the GDL then you might wnat to consider doing the lPC in the same place as you are settled by then, unless ofc you fancy a move. You may strike lucky and get a TC and a firm willing to pay for both. Law can be very ccompetitive when it comes to getting a job.