He has looked pretty good in the Olympics. I am pretty skeptical about Mahinmi becoming a regular contributer this season. He will have a tough time staying out of foul trouble and just adjusting to playing against the elite athletes in the NBA.
Javtokas is ready to go. Averaging just about 20 minutes per night in the Olympics he has been a solid contributer. He is hitting 70% of his buckets and pulling down 5 boards. He has also averaged just under 1 block per game. He would be nice to have on the team for insurance in case the geriatric KT comes up gimpy and/or Ian shows that he needs another year of D-league. He is 28 years old and he has pretty decent size at 6'11" 250.
Oh wait. He has a 1 more year left on a contract with Dynamo Moscow. The chances of the cheapass (and to be fair near the cap) Spurs buying out his contract and paying him more than he could make in Europe are about zero. He'll probably end up a Spur when he is 35.