Thanks @ all for the comments!
Steve, Grobya is one of those genera which have been jumping around Catasetinae, Cyrtopodinae, whatever... "Recent" phylogenetic studies have shown that Grobya, as well as Galeandra, belongs to Catasetinae (actually, they are very close to each other in the phylogenetic trees)
In theory, Grobya should be grown similar to Catasetum, however I cannot give much details yet, as this is a new Genus for me... I have Grobya galeata and Grobya amherstiae since less than one year... so far, I have not seen that they are "real" deciduous plants, as sometimes reported (other reports go for not deciduos plants!). I am growing them with my other Catasetinae and tehy seem to like it
Watering a bit different, as I grow my other Catasetinae in S/H or PET (Brazilian version of S/H, using organic substrate and adding slow-release fertilizer <- will change to this in the future, as I have seen they like it A LOT better!)... I water Grobya when the substrate is approaching dryness...