The challenge when looking at powered/active monitors is understanding the difference between studio monitoring and home use speakers. Any good speaker should have a high level of detail with good timbre.
Studio monitoring is work. The purpose is to weed out all the imperfections, so while the frequency response can be expected to be flat and imaging is solid, the sound is dry and un-involving (typical sound from Mackie, an unremarkable inexpensive monitor). Being active design they tend to be very dynamic.
Home use monitors are typically not used in near-field settings so room effects should be accounted for. The purpose of home listening is to derive enjoyment and making an emotional connection.
Keep in mind that powered speakers are simply passive (normal home speakers) that have have the amplifier chosen by the speaker manufacturer and normally installed inside the speaker cabinet (often the amp for both left and right channels are in one cabinet). Active speakers also include the speaker manufacturer chosen amps, but use one per driver. This allows for direct synergy between amp/driver and a low voltage crossover than can be more precise and include DSP. Active designs are dynamic, have flat frequency response, and greatly extended bass.
Most powered/active monitors are intended for studio work. The exceptions include Audioengine 2+ or 5, and PSB Alpha PS1 (all powered, but I'd recommend the active Tannoy Reveal 402 instead); Adam F5, F7, or A3X and Focal CMS 40 are all moderately priced actives ($250 - 425 each); Adam A7X, Dynaudio BM5 Mk III, Genelec M040, or especially the Neumann KH 120 ($730 - 900 each) are all well respected actives and a very nice step up.
