With the model progression of the MF integated ... which would be A300 to A3 to A3.2 ... the MF sound has been tweaked to become more detailed and analytical.
I originally owned a MF A3 integrated (gold trim) and have since upgraded to a MF CD PRE24 (combination preamp & cd player) and a MF A300 power amp. The move has worked out well, even though I did not originally start out to have separates.
I always liked the MF A3 integrated ... I found it to be an elegant and pleasing sounding amp. The 300 power amp though, is just as detailed, but has a warmer, richer sound to it and it drives any speaker load with ease. I always thought that the MF integrated was working hard (though not quite straining) even when playing music at lower levels.
Also, keep in mind, that your options with the A3 integrated are pretty limited, when it comes to switching in other components. The A3 does not have a PREAMP OUT and will not allow you to use a separate preamp. I found this out the hard way, as I just assumed that the A3 had a PREAMP OUT ... which is how I wound up ultimately with separates.
Not to spend your money, but if you were looking to upgrade your CD player and wanted considerably more power, as well ... for about $3000, you could get the CD PRE24 and the A300 power amp, new, from Upscale Audio
. It would represent a very noticeable upgrade from the A3.
So, you will notice a worthwhile difference with separates and if you shop around, you will have some options.