the extra-time-to-put-on and stepping-on-upholstery arguments are kinda dumb, at least for me. Sorry to say. I put my boots and bindings on all on the swim platform and it takes me about 1 minute to get them on, lace up, and strap down. No boots stepping on upholstery at all or crawling anywhere. If you think 1 minute is "too much time" to strap in to these boots then you might want to loosen up your schedule.
also another pro to the systems that hasnt been mentioned is longevity. give me any traditional boots from any company (including hyperlites non-system boots) and after riding them for a month or two, they will turn into mashed potatoes or socks from a support stand-point. My systems from last year work just as good as the day I got em, granted the boots are more broken in than before, the support still remains from the bindings, I just click down a few extra teeth.
Yes, they are difficult to swim in. but the boat usually comes back to you to pick you up at the end of your set, no issue there. at the cable i swim to shore with my boots still strapped in, then unclick at shore. that may be a little more work sure, but its worth it ten-fold IMO.
comfort, support, response and longevity. for me the pro's outweigh the con's and thats why I wouldnt trade them for any other bindings. hope this helps.