Was able to delid the chip again using razor blade, used grizzly this time and temps are improved! Turns out I hadn't tightened down the waterblock enough.
Haven't resealed it this time so chip will now be sold delid
Vantage X imho would be the one to pick if we had to pick one of the two (H or X) since X runs 1920*1200 vs 1680*1050 and the CPU is weighted 0.05 vs 0.15