Go for it.....
As all things in life it is all about compromise.
Gearing and Jetting are your main considerations.
Street gearing for the 300 would be 14/42..... dirt 14/50, so find the happy spot in there that works for you. Myself I am going to try 15/50 today.
I have put on about 80 000km of Dualsport mileage using 2T bikes ('89 DT200's and KTM300's) and have never had a issue other than missing the ideal jetting mark on occasion. These motors perform flawlessly and if it does go wrong are super cheap and easy to fix. Never will I own a 4T
...just despise there complicatedness and weight. Beside I want to ride ....not work on them.
Plate that 300 and join the 2T DS crowd...