Martinez.I originally had a model 8(no T).My friend had a model "T",which sounded better to me.I then had the update to the model "T",which was a big improvement.
To my way of thinking,the 8 and 9 series of Rowland amps were overdesigned(a good thing)for High End audio.To me,the new stuff(model 300 etc.)while probably great,is still designed with an eye towards the home theater market.They are lighter,and more compact.
You can ask the Rowland factory,as to the cost of updating to a model 8t/switch mode(2 mods in one)and they can,also,give you ship costs.Remember,the ship cost coming back to you will be much cheaper than the cost of shipping to Rowland,because the unit will be lighter.It's all up to you.Good luck!!