It's a commonly asked question, as is the one of adding these hours into ones total time.
I think 18 greens has summed it up correctly. Airlines need to put ticks in boxes when it comes to handing out selection places. One of them is a suitable licence (read CPL/multi/IR frozen ATPL) here in the UK. If that is what they want and that is what you have you get 'that' tick in 'that' box. Total hours may (usually is) be another box that needs a tick. If they are looking at recruiting very low hours straight out of training pilots then it makes no difference if you have 200 or 300. If you include sim time in that total I think you could run into trouble, especially if they want (lets say) 500hrs TT and you claim 505hrs of which 50hrs are sim time from your IR/MCC/JOC etc. I think you don't meet the criteria set down and are in danger of being thought of as trying to claim more hours than you actually have.
If you don't agree then why not go and do another few hundred hours in an FNPTII sim and bump your total up that way, much cheaper than paying for a real twin aircraft?
Airlines are not interested in sim time. They want to know how many 'real' hours you have and that does not change as you get more experienced gaining type ratings and airline time; when it comes to dishing out commands I know of no airline which considers a pilots now (not inconsiderable) total number of hours in full motion sims.......................
I'd go for what suited me best. If you get more aeroplane hours than another course for the same price I'd take that course (all other things being equal), but it may be that other factors come into the decision, like if you live next door to one training provider it may be that what you save in living costs makes up for the lack of aeroplane hours (and possibly allow you to spend some of that money on something after the multi/IR).
Best of luck whatever you choose.
PP