I dunno...I do not think I would "ditch your Sony" unless you can find something SPECIFIC, that you cannot do within Sony's system.
like work with pocket wizards, find rental places in any major city, find a first shooter or assistant that uses a similar system, have the backing of a professional service like NPS or CPS, local dealer support, confidence that the system will still be around 10 years from now (remember Minolta, and Olympus E-System?), oh yeah...and the backing of a real Camera company.
When one needs to rent "the basics", one is seriously,seriously under-capitalized. Unless one needs a 400/2.8, he ought to OWN the lenses needed for a HUGE percentage of assignments shot on 35mm-style d-slr gear. Pocket Wizards can be made to fire on any camera that has a PC socket, or with an adapter from Minolta/Sony to ISO...$15 per adapter....I'd HOPE a "pro" could figure out how to make basic cabling or basic shoe-hookup equipment work.... So that Pocket Wizard strawman is dead,dead,dead.
NPS or CPS backing really isn't much of an advantage for most professionals and the maiority of non-sports, non-PJ people are not members of either service, so another strawman shot down.....NPS has become a joke--unless you're at the Olympics, or the Super Bowl. On a regular assignment, like shooting a regular-season west-coast Pac-12 football game, NPS or CPS Services probably won't be able to give help for rank and file members.
Again...if you need to "rent" 35mm-style d-slr gear for regular assignments, you are seriously under-capitalized. An "assistant" than cannot handle a Sony d-slr isn't much of an assistant to be worried about. The system has been around in Minolta, and then Konica-Minolta, and then Sony forms, as the "A" mount since autofocus began...so it's been here since 1985 or so, which is only like 27 years of continuous production of lenses, flashes, and bodies using the same mount.
Local dealer support? In this day and age, one is more-likely to get better, faster, lower-hassle service from
B&H or
Adorama--or even Best Buy. "Local Dealers" do not even exist in many small towns in the USA...they went broke a decade ago...one's chances of getting "dealer support" are better at Best Buy in many localities...I know places here where one can drive 150-200 miles and not be within 100 miles of a "dealer"...but where a Best Buy is within an hour's drive...or less.
Of course, if a guy wants to construct imaginary roadblocks, manned by straw men, he is free to do so...it's pretty easy to imagine hypothetical situations and try and put the brakes on somebody else's plans. But my contention is that two bodies and FIVE quality lenses, a couple flash units, and some studio strobe gear and "most" professionals would be able to complete well over 95% of their normal, "everyday" assignments that use 35-mm style d-slr gear. Without the need to rent anything.