Allison Pregler is my favorite reviewer. The only two that come close are Grace Randolph and Lindsay Ellis. Movie Nights (formerly known as Obscurus Lupa Presents) is a ridiculously entertaining review series where Allison Pregler (Lupa) takes a look at some of the worst movies ever produced, as well as an assortment of her own favorites, and a good amount of cult tv. Her crowning achievement in my eyes, is her Charmed review series.
Charmed, was a WB show that debuted in 1998 that I was a fan of when I was younger. Allison completely dissected it and came to so many hilarious conclusions about the show and made one of the most incredible and extensive reviews in history in the process. Her season eight review was a two hour long epic rant on the final season and the show as a whole. Even recently she released a review of the first season of the Charmed comics published by Zenescope, and it was equally hilarious, and showed Allison's proficiency at reviewing different mediums.
Although Charmed is probably her best and most extensive work, Allison puts so much effort into all of her reviews, and some of my favorites include her Star Trek episode reviews, First Person Shooter (The X-Files) review and her reviews of the Tremors series of movies and short lived tv series. Movie Nights is well-researched and often times hilarious.