Bought one after playing with UTG OTB bipod to test concept.
GRS is a solid bipod, well built and sturdy.
I have found OTB bipods to seem a bit more flexible when loading vs. an under-bore bipod (Harris, atlas, etc)
i also found that I don’t need to load it nearly as much as under bore types to get good recoil control. The rifle hanging below spigot seems to naturally find balance, holds POA . It may tip easily (as observed in above post) but I was able to easily correct that. i am able to see my hits and misses more easily in field, and another plus is rifle much less prone to falling over on uneven ground, etc. it seems to take a POA with less loading pressure than UTB bipods.
for match shooting and field use I use OTB strictly for prone. Ill use atlas for barrels, roofs, etc. I am experimenting with turning OTB spigot 180 degrees and hanging rifle under bipod, eith the inverted legs supported by tank trap legs. just another option.