Chrysler Repair: 300M limp-in mode problem, solenoid pack, solenoid switch

Question
QUESTION: Hi, my 300M special (2004) intermittently gets into limp mode while driving.  It recovers when a power off / on cycle and runs good again.  It happened about three times in 5 days so far.  The error code from the mechanic is P1776, Solenoid switch valve stuck in LR.  The mechanic asked me to do a transmission flush first, then, may be a complete overhaul on the transmission. I have spent over $5000 last two years fixing it already, don't know if I should write it off?  Engine has 250K miles and runs perfect, body in the best shape ever.  Thanks tons for helping.

ANSWER: so what do u want to know  if it worth fixing  or what u should do to fix it?

---------- FOLLOW-UP ----------

QUESTION: Thanks for answering.

Well, I am sorry not making my question clear the first place.
Let me rephase it again.  I did some research on the Internet and seems like a solenoid pack is needed (roughtly $700 parts and labor) but then, what is the chance that it will be fixed?  If not, I might be down the road to continue spending as the dealer won't guarantee 100%.  In fact, they will replace one after the other until the problem disappears!!  So, what do you think the chance of fixing after the solenoid pack has been replaced or if there can be several causes other then this that gives me surprises?

To wrap up as a used car owner, can you enlighten me on how often the real transmission will cause problems on a 300M, under constant dealer maintenance?  I figured out if the engine I have good faith in it, the only thing for the coming two years that I need to worry would be the cost of a transmission rebuild (even after the solenoid replacement now).  I wish to forecast the cost of operating this car for another 100K miles to justisfy the present spending.  

Again, thank you for your help.

Eric

Answer
with out seeing the codes myself or seeing pressure readings and or sensors readings at the time of the issue  I can not give any sorta of advise if this will correctly fix your issue.

The second part there is also no way for any one to tell u when something will go wrong with your car at any given time