A bit optimistic to expect consensus among anglers, Situasian!! Whether its boat formats, rod and reel brands, lines, soft bait styles, etc etc, you'll get strong and usually divergent opinions.
But it's certainly worth asking for input and then making a judgement call.
There are a number of factors which people weigh up when deciding the benefits of overhead/baitcasters v spin in terms of inchiku fishing. The key ones seem to be:
- the drop - how to detect takes, and speed at getting to the bottom
- letting out line as you drift, to keep your lure on the bottom (thumbing overhead v bail arm open and closing, unless you hold the line in your hand?)
- speed of retrieve
But even experts like Paul Senior - who did a lot to popularise inchiku fishing - waver. In all of his early articles on inchikus, it was all overhead/baitcaster for Paul, end of story. Then a couple of years ago he did a total u-turn - mainly based on the speed at getting to the bottom when you arrive at fish. With no tension on the line, your lure will get to the bottom much faster with spin reels, and probably wind up faster as well, either for a re-set or with a fish on.
The top spin reel exponents are able to detect takes on the drop by spotting if the line either stops or speeds up.
Another factor for some people is the way you hold the rod during fish fighting - underhand or overhand. Some people prefer the leverage of spin v overhead.
I use overhead in the work-ups, but the best snapper I've seen caught in Hauraki Gulf work-ups was a genuine 20lber on a spin set-up, by a very lucky woman angler.
Good luck with the new set. I've got that reel and it's a sweet operator. I'd recommend you don't go much heavier than 10lb non-fused braid - such as Sufix 832 or similar. Less drag in 40-50m of water, and more than enough grunt.