on the architecture, the difference between the two is only on RAM and chipset. if Asrock DDR3 and CPU Socket 1150 then TB250 DDR4 and CPU Socket 1151. Asrock H81 cheaper than TB250 but TB250 has the M2 slot for can used add a GPU again. in the performance on mining both the same good.
if you want to save a bit money, you can choose Asrock but if you want to add 7 GPU you can choose TB250 and buying M2 to PCIe adapter (if using M2 slot)
TB250 BTC is OK, but there are sometimes compatibility problems with cheap M.2-PCIE adapters