I don't know enough about lands to say with absolute certainty. What I would do is weigh the ROI you hope to get from lands, lower that estimate by about 30% to be conservative, and factor in how likely that is sustainable long enough to recoup costs and start turning a profit.
A lot of it's a gamble. I don't see the 20% interest on HBD changing as much as the income generated from lands.
RE: Should SGS Buy Land in Splinterlands?