Right, I've tested it on Very Easy. On the whole, it's quite an improvement over retail AI.
In Apocalypse with the new AI, I encountered little difficulty escorting the transports. The only ship I did lose was one of the Lambdas. My wingmen had a few issues coping, though. Here's a summarised casualty list:
I started this mission off in a Herc II with three wingmen also flying Herc IIs. Beta Wing comprised of 4 Ulysses fighters. Gamma wing comprised of 2 damaged Perseus fighters, and Theta wing comprised of 4 Serapis fighters.
At the end of the mission, the following were dead: Alphas 3 and 4, Beta 1, Gamma 2 and the whole of Theta wing. If anything, it's proof that flying a Ulysses in the last mission is probably the best way to go.

...But Hate the Traitor was real fun. With retail AI, it's a cake walk simply because they're forever flying upwards when you're behind them, but with this new AI, it's both challenging and fun. It took me a lot longer than usual to kill Alphas and Beta. More notably, they know when I'm on their six, and when they do, they start making quick, sudden changes in their trajectory to prevent me from successfully leading them. I had one of them in front of me for a very long time, and I just couldn't hit it.
It was still pretty easy, though. I lost only 15% hull on that mission: 1% to a collision, and 14% to the Saharan's AAAh (I can never evade that).