If it's spongy, you either have failing hoses or air in the system - professional mechanics don't always do the job very well because they rush or because they have no personal investment in doing the job properly. In the UK, most garages do a terrible job, including franchised dealer workshops.
My feeling is that it is one of the above or a suspension fault (bushes being the likely culprit, allowing the axle alignment to move in relation to the chassis) - I know a LR specialist who bought his wife a brand new D1 years ago, and it occasionally lunged across the road into oncoming traffic under braking; they found the radius arm bolts had never been tighten up and the axle was moving by 2" at one end.
If the suspension is all good, check the swivel pins and bearings and the steering rods and rod ends. Have a close look at the steel/copper brake pipes to make sure they don't have any damage or crimps from excessively tight bending, off road impacts or being bashed by tools while servicing.
If they're all good, swap the brake disc and pads (don't intermix them) from one side to the other and see if the pull swaps direction. If that makes no difference, swap the hoses over and try again.
One other thing - make sure the callipers are a matched pair; an LR owner in England had a badly maintained and modified 110 with rotten suspension brackets, a trailing arm that was 1" shorter than its counter part and mismatched callipers, plus a raft of other defects, which resulted in him crashing his family into a drainage ditch and drowning some of his kids. Google "Gresham" if you want to read more about it.