Pinnacle - I have the M230 all the attachements except the pole pruner. The edger works fine and the hedger is awesome. The power head has been trouble free, now it's it's second season.
You might also want to consider their new split-boom unit that's 4 stroke but takes an oil mix. I think it's the M2500. Supposedly it has a little more power than the 230. The 230 power head is a little small for the power broom attachement, but does well with all the others I have.
Just keep in mind that if the power head goes down for some reason, you have multiple tools out of commission.