I too have had all three.
The Lowrance with the structure scan had the best imaging, but not by much. The extra money and set up made that choice questionable, unless you are hardcore or a guide.
Once you choose the total scan transducer models, I cannot tell the difference. Do note that the Simrads are made by Navionics , the same company that makes Lowrance. Check to see if the Go9 is cheaper than the Ti because they are virtually the same. That is what I have had on my boat since my Garmin crapped out. (The Garmin replaced the Lowrance that was stolen. The Lowrance replaced the birds I ran for years. BTW, I found the Garmin warranty/repair service very poor.)
My next change will be back to the 'birds. I plan to upgrade the troll motor to the Ultrex with the mega down image built in transducer and Ipilot link. This means a mega di bird up front and a networked si bird at the dash. Sadly that combo, with the Ultrex, runs a bit more than your $2000 target.
I do not know if that information will help you, but it is what I know.