Since SOME casinos have now made it easy to track wagering, this puts those that don't at a disadvantage. If support are good at responding FAST, this is not such a problem, but where support takes forever to reply, it is very offputting.
King Solomon said to me that the WR indicator caused problems because of a bug where players would make a fresh deposit & the WR from a "dead" bonus would reappear, causing them to wager too much!
However, better to wager too much than too little & get shafted by harsh rules.
The MG system is best (apart from the bugs), as you do not need to go to the cashier to see if you have completed WR or not, and because the bonus converts to cash in 10 credit increments you can even work out how much WR is left. The cashier will present an exact figure.
Using hand counters & other methods severely reduces the enjoyment of playing (unless the ONLY purpose is to take the bonus), and is only necessary so as to not constantly bother support, and avoid those places that will screw you just because you were out a little in working out your wagering.
Since the bonus model is extremely popular as an online marketing tool, it is odd that it has taken so long for the software suppliers to implement something like this in the software. This brings operators under suspicion, such as did they deliberately suppress such developments in order to produce reasons to delay or deny payments, there are certainly a few casinos that do this- even to the extent of having CS lie when players ask if WR are completed so as to confiscate winnings at audit.