My understanding in the "G" limitations was based on what I had been told and this came from someone who had read the Flight Manual. Perhaps they were quoting the flap down figure. This person (a very experienced instructor) expressed a very real concern about operating the P2006 in turbulence. The very fact it's a twin which will be used for IFR training means it will experience it's share of thumps and bumps especially when IMC.
I do know that one local P2006 has suffered damage to both engine mounts presumably through turbulence.
So far as for it's usability for multi training is concerned, as an instructor I find being able to carry more than just the student and instructor can be a very valuable way for other students to learn. If the payload is limiting such that is not possible to carry observers then it's usability is somewhat restricted IMO.
I hear you can brew a cup tea in the time it takes to cycle the gear. Could be a bit exciting if you need to get the gear up in a hurry. There's no squat switch I hear, what happens when a long legged student bumps the gear switch with their knee? The main gear probably won't be able to move, what about the nose gear and damage to the nose area?
About the only thing going for it is the fuel burn. There are some very good second hand twins that can be purchased refurbished and re-equipped avionics wise and still have plenty of money left to pay the higher fuel bill, when you look at the purchase price of the P2006.
I've had a look at the P2006, the aircraft is lightly constructed and IMO will not stand up the beating the can/will be given to it by students as well as other twins like the Duchess or Seminole. Also the Rotax engines are getting expensive to overhaul.
I've been involved in operating and owning aircraft for over 20 years and I stand by my statement about not wanting to own or operate one long term.