I don't think it makes it any more difficult to work on the engine - but if you are used to putting a socket on the dog bolt to turn the engine then yes that is more difficult, if not impossible with the yellow fan.
For me, I have absolutely no regrets to switching to the yellow fan. My metal fan was out of balance, wobbled, and was noisy at idle. I also saw improvement in engine temp after switching the fan out which was a big help in the Texas summers.