LOL, it like another discussion, using burst mode are noobs, using singleshot drive and manually burst with ur finger tapping are Pro.... so, use manual!
shootkk: (or anyone else): shootkk, this is not directly to u, but just MY Opinion (u can choose to ignore)...
to me, those mumbo jumbo talk and discussion are pure crap, its just talk to make u sound smarter, not shoot better. there is no right or wrong in photographing or making painting shooting editing tak'ing' or creat'ing', magically appear'ing' or anyth'ing' to do with a photo.
the arguement saying u use prime u are better? or more pro, or better learning or
'classified' u as better? that is big BS to me. i do not expect myself to swap 200mm, to 85mm or 35 then 20mm during a wedding job. does that makes me a noob(ok not so harsh, but 'taking') a picture?
journalism may use prime* but of all journalism photo i see, non are super nice(iq) as those shoot for advert in mag by zoom lens. how to justify?
coming back a little to the discussion point, zoom lens gave people versatile, not title of 'taking a picture', technology is so wonderful, use it... impossible u know u have 7fps, u go use single shoot drive and manually use ur hand to burst because using fps is noob mode?

alright...
(my opinion of primes is they can get better aperture then standard zoom, although tech had let zoom caught up with F2.8(up to 200mm)... prime is when i do need the aperture below F2.0)
okay, serious talk here: there are people, who are experienced (who i like to call pro) knows a 'zoom lens' like knowing their wife... coz, when using a 24-70 F2.8(lets say), when shooting a subject, they know how much they need to zoom (distance vs zoom plays a role in determine DOF without changing aperture) and still walks in front to compose with the 'zoom' then set the appropriate required aperture (dof) to shoot... , like i said before, zoom are versatile, many learners might just did what u quote, "
you just zoom in and out until something looks good" but how many would next think about the DOF appearing to the result? who many would turn down to F8 to shoot at 50mm?(so u get the subject, perhaps small or big but near to be sharp)
prime or zoom lens do not give u(not u shootkk) right to brand people...
*edit; eh, i check there is not [ spoiler] in my reply, but why is my reply spoilered? lol
*edit: fixed, thanks to the mod who helped...

Not to add to the debate or argument. I Personally think to use a zoom lens, one needs a lot of self awareness. Needs lots of training to really master it. An example of a basic exercise i get to try during my design school... where one was given a restriction to improve our creativity.
we are given 3 forms: example 1 rectangle. and 2 circles. We are required to create 50 interesting combination using only this 3 forms. I like the exercise as it force us to think out of the box. Although we struggle at first but we soon realise we can create endless interesting forms using just the most simple primitive forms. If we are given too much freedom... we will have no proper direction. Site dimension constraint. Budget constraint. Forms constraint. In architecture we work around it.
Anyway what im saying is... I love using prime to challenge myself. is just my way to play with my camera...although sometimes no choice i still have to use zoom. this doesnt apply to everyone of course.
I guess your statement contradicts. You were asking which combo is good, Siggy 50mm + A850 or 35G + A700, the obvious answer would be Siggy 50mm + A850. If A700 can fulfill your requirement, then you should discard your question considering your A700 is fine for you for the time being.
With the same theory, by getting a 35G wouldn't help you to improve your photography much too.
35G is not worth to get, A850 + Siggy 50mm f1.4 is a better combo as a walkabout lens.

That is just a quick thought of the day.. just curious whats d difference between this both combination... since both also almost same focal length. Will fullframe really make a big difference in this case? I could b missing something for sure. is for my education purpose. i nvr really think of spending 5k on a 35G or A850 anytime sooner anyway... but is good to find out.