Hi, well, everybody has different expectations, so it is hard to answer without knowing more precisely how you want do practice IFR. I would say, X-plane 11, in its current beta release, is as useful as XP-10 was (ans still is) in terms of IFR practice. That said, you might consider building your own opinion by browsing youtube as many many videos are available.
As an example, I use a set of 2 Ipads to simulate both screens of the G1000, using Simionic Hardware and software. All this works extremely well since XP11 has been prereleased.
But you do not need all that to have a satisfying level of IFR simulation. I find XP11 sufficient on its own.