My collection page is not complete, but I'm trying to update it.
In terms of review scores:
90+ = Exceptional, a must-have for any enthusiast
80-89 = Solid release, possibly a classic, certainly worth a purchase
70-79 = Flawed but appealing, worth a download
50-69 = Average or mediocre, don't waste your time
30-49 = When the cons outweigh the pros, trashworthy
29 or less = An absolute travesty, berate and defile this album in any way possible
It's important to note that often what the average reviewer will give an 80, I will give a 70, so take that into account when looking at the scores.
I'm a big fan of old-school death metal and thrash. Once in a while I'll find an exceptional album that falls outside those two genres, but it doesn't happen all that often.