Lots of pros for microinverters already listed. I'll leave Andy to posting about all the negatives.
I originally went with Enphase microinvereters because I was DIY and figuring out string sizes, code requirements for DC wiring, designing the system, picking an inverter, etc. was making my head hurt. I also had some significant southeast shading that I figured they would help with.
This turns out to have been a great idea because my first phase of 21 then turned into a second phase of 35 more which included adding one one more on the south roof, 4 more on the west roof and the rest on the east roof. Then that turned into 15 more. The simplicity of adding more with a microinverter is a pretty nice benefit if one is leaving roof space. I also appreciated that all the wiring was just standard 240 volt stuff (except for the special grounding requirements) so it make it simple using my existing skills.
Now I'm producing more than 100% of my usage for an EV, and heat pump space and water heating.http://kemp.solar