I bought two brand new seiko 5 watches before. Great looking but first one breaks down after I remove the movement for hands mod and it stop running for no reason. The second one keeps horrible time of 3min fast per day. I sold to another guy still with warranty left.
Then I decide to buy seiko superior diving series. Took the movement out for mod, great, no problem and keeps decent time of 30 seconds fast per day.
But all my invicta with seiko automatic movement outperform all my seiko watches. Bought a yellow grand diver and do mod of relume. The watch keeps superb time of 6 seconds fast. Recently, bought a invicta pro diver with seiko NH-35A and it keeps 3 second fast only after 2 days.
I know plenty of seiko supporter in WUS. But this is what I experience with seiko watches. I have no doubt for high end seiko but I am quite disappointed with seiko lower end automatic watches. And even more puzzle that cheaper invicta watches can do a better job with seiko supply movement. My experience with other Japanese watch maker like citizen are far better. No problem at all.