this is my first year... and I use compost tea now and then... but I was using that before with peat based starter or pro-mix... I could never find the pro-mix with additives around here.. unless they were the small bags.. so I never bothered to try them... I would say it holds more moisture.. and drains better.. but I use polymer gels with everything so I am not a good judge ... in my mind using a few in the bottom of the cells is the same as bottom watering .. but I have been doing that for a few years now regardless of what medium I was using.. never really share that much because I know some seed people would think I was nuts for using gels with seedlings
here is a photo of my babies today... ignore my leggy dahlias in the back.. I always start them too early and do cuttings of them.. which is over due now.. having a lazy seedling year