I have spent some time going over the nice images
@John Galt posted and must thank him again for that.
so base on specs,
@KEW did a nice job comparing the two (A300 vs M2200).
Based on the info shown by the photos, one can immediate see the following differences, though there are doubts on the Outlaw's PS capacitance and the transformers current ratings for both units.
A300:
- smaller transformer, lower voltage also, 43.5 V vs 53.6 V, that means the difference in max output into 8 ohms between the two should be a little more than 150 Vs 200 V as (53.6/43.5)^2 = 1.5183, so if the A300 is rated 150 W, the M2200 could be rated for 150*1.5183 - 227.75 W.
- Apparently a little more P/S capacitance, 2X10,000 uf (see Outlaw's below)
- Have two fans, and the heat sinks are obviously undersized and therefore the fans are needed, and as John already confirmed, will fire up when in use.
M2200:
- As mentioned above, the TX sec voltage is rated 53.6 V, that gives it an advantage in driving 8 ohm loads.
- The VA size seems limited as the current seems to be rated only 4.5 A, I have no idea how it could be rated 300 W into 4 ohms unless that 4.5 A on the nameplate is not really the maximum rated current. Hard to say without seeing the full data sheet.
- The heat sinks look much beefier than the A300, even for class AB, let alone it is the fact that it is class G.
Overall, I would take the M2200 for $299 each when on sale, especially for driving 8 ohm nominal speakers. The A300 may be do better, relatively speaking, for 4 ohm speakers but then you would have to put up with the fan noise. So in the end, the Outlaw with a fan on top may still be a better way to go.
I can't really say too much more without seeing the data sheets for the PS transformers and confirmation by Outlaw on the blocking capacitance.