(A review to fill the void of no reviews):
OVA's not based on missing manga chapters usually fill me with dread... but this one was a very reasonable attempt.
If you like the comedic parts of Hiakyuu you'll enjoy it. If you prefer the sport side and are filled with annoyance when the plot doesn't have any volleyball in, then you might find it a bit lacklustre.
+ it made me laugh
+ good slice-of-life vibes
+ few good character moments
- it's a filler episode (good for an OVA, but you might disagree)
- no sports (it's just a school/exam prep episode)
5 to 10% of this OVA is repeat footage, but the rest is new additional context. If you don't watch it you're not missing out on anything, it's pretty clearly just filler.
Some comedic moments, some good character moments, almost no volleyball. If you're desperate for more Haikyuu content definitely give it a watch, but for me it was just okay.