I used both RANT 2000 and Flitepro for my IR training and I found them a great help. The big bonus is it gives you something to practice on for free.
Both require some time to get familiar and as it has already been said, RANT is not a joystick flown programme. However, RANT has the great advantage that you can fly a proceedure perfectly and then print it out. For example, all the RANT turns are exactly rate 1 so you can see what the instruments should show if you flew perfectly. I found this a great help when trying to sort out holds with strong crosswinds.
Both RANT and Flitepro have HSI/RMI but the aircraft choice is limited to only two with Flitepro, a Bonanza A36 and a C172. You are therefore stuck with these.
I managed to burn all the checks into my brain by repeated flights using Flitepro and this may just have staved off bankruptcy which I nearly encountered at the end of my IR.
In many ways RANT version 3 was easier to use because it came with an instruction manual. RANT 2000 doesn't have a manual so there is no logical sequence to guide your learning. In my opinion it is a bit of a con to sell something for this price without an instruction manual.
One final note, Rant is the only programme I know that simulates dip on the ADF. It is slightly unrealistic in that it snaps back quickly at the end of the bank, but its still useful when you are trying to sort out what is going wrong on your NDB approaches.
Like all programmes, you have to spend time to find the best out of them.