Thanks for taking the time to provide all this valuable information.  One other thing to consider with the Maxi Sys is cost to update  if you always have to keep your car coverage current every year like if you work at a dealer and considering the Maxi Sys Elite or Pro, and won't see much use for the BMW, Mercedes, and some Audi programming from off the tablet. You will be setting yourself up to pay $1200 a year to update it  versus only $700 for the non J2534 equipped regular MS908 ,MS905 Mini, MS906 BT and TS that be about $500 less a year if you had to update or restore software unexpectedly became corrupted or unusable after your subscription expired and you are now forced to buy an update since Autel provides no recovery partition for car software or clear instructions on creating restore backup software like users of old DS708 could. That extra $500 a Pro or Elite costs to update each year is for one year Server access to BMW, Mercedes , and Audi J2534 programming files and Autel will not let you downgrade a Pro or Elite update subscription to a regular MS908 to save $500 to update if you are hardly ever doing programming on those 3 makes of cars to justify the extra $500. If you have a regular MS908 that is out of free update period and you buy the Maxi Flash Pro, Don't  decide to play with it and pair the J2534  to the regular 908 out of update period .
  Guess what ,
   You just made your regular MS908 into a Pro and your update cost will be $1200 instead of $700  and there is no undoing it and going back to regular 908 update costs.
    If you are fortunate enough to not to have error of WIFI MAC not matched or no longer authorized to access and use  the regular MS908 software  and forced to pay $1200 for an update to get problem resolved and are still somehow able to  use it as a regular MS908 with the Maxi Flash Pro  J2534 paired , you are likely still  not going to have  access to the Autel server for any programming files for   BMW, Mercedes , and Audi unless you purchase a 1 year MS908P subscription for $1200  

 Is the maxiflash listed in the hds as a com choice and immo function online or through maxisys

I have done gm online 2010 to 2012 so far,maxiflash listed in com choice, immo online

tech2 wont do immo online past 2010 ie equinox but did flash pcm

 Is there any PROBLEM with any manufacturer?

 Yes, getting the Chrysler program working on 2009 and older cars is a bitch! That's not Autels fault, the j box works fine. It's Chrysler's program.

 dodge is complicated . need to add sites