Joshidai: Ecchi Soudanshitsu, Tsui no Sora Recommendations
These hentai OVAs are unique experiences, to say in the least. Their aesthetics are very comparable, with similarly poor art styles, simplistic coloring, and drawn out usage of repetitive frames that result in h-scenes being very static.
Add that to "lackluster" stories and these are easily some of the most "impressionistic" hentai (and anime) that you will ever watch. However, it is certainly possible for them to also be the "best" hentai; if you're feeling masochistic, demented, or simply whimsical, then these may very well be some of the greatest things ever.
Basically, their adult content is similar. The weirder of the two can
Both are crap hentais with terrible animation, nonsensical plots, horrible sound effects (when a sex scene appears, a crepe paper being crumpled sound plays), and they does not show the animation studio in any part of it.