Hey!
I've owned four Omegas, two currently, and I own a Seiko SPB087 PADI, which is such a beautiful, fun, toolish diver that I wear very often. I'm wearing the 087 on an Erika's Mirage with white stitching today. I have nothing bad to say about the 087. Seiko can really dish out a nicely finished and well proportioned watch. Also, I gravitate towards aluminum bezels.
I was very interested in the SPB143 before I got my 087 and I spent a lot of time researching that model, as well as the SPB239, which is a variant. The SPB143, its variants, and a few other Seiko model lines are reinterpretations of the antiquated Seiko 62MAS diver. I think they are really cool looking watches. The SPB143 might be considered a step up from my SPB087 in the Seiko hierarchy. Compared to it, the finishing on the SPB143 seems a tiny bit rough around the edges and it just seems slightly unperfected...just my opinion and difficult to explain. On a 62MAS reinterpretation that's kind of working for it. Definitely check one out in person to gauge how you feel. The SPB143 also has some production issues. Bezel alignment out of the factory is hit or miss, which can be adjusted. More disturbing is the chapter ring alignment, which is also hit or miss, and worse, is a function of printing (apparently) and can't really be adjusted. It can be pretty bad on some examples. Hardcore Seiko fans seem to wave this off, which is just silly on a $1200 MSRP watch. Then there is the bezel pip, which I think is done somewhat roughly and, again, is hit or miss, as it can be malformed, which looks really bad to me. There is also the fact that, due to a sudden mid-production design change to meet an ISO regulation that requires a lumed index at 3-o-clock, they killed the nice looking beveled date window and threw in a runty offset index, and that really hurts the visual balance of the dial and the watch as a whole, in my opinion. This has caused the early examples with the bevel to become a bit rarer and harder to find. Also, the caliber 6R35 is really not a premium movement, not even close to the Spring Drives, as 7enderbender mentioned. I don't think the SPB143 is worth what they're asking MSRP. But if you like the watch, you like the watch.
If I was going to purchase the SPB143 and I didn't care about the design changes they've made, I'd want to do so at an authorized retailer so that I could inspect what I was getting very closely and get the full warranty for the 6R series movement. Otherwise, I'd be extremely diligent looking for a pre-owned early model with the beveled window and good alignments while trying my luck with any remaining warranty. But note that having Seiko service a 6R35 out of pocket is much cheaper than having an Omega serviced. Right now they are quoting $260 for any 6R series.
Compared to the 2254.50, which I've personally owned, there is no contest whatsoever. Execution, quality, and the caliber 1120 on the Seamaster are all well above and beyond the SPB143. That's obvious. You clearly know that; I thought I'd reinforce it.
I *just* joined this forum (hello to everyone!) and I'm not completely sure what is allowed regarding image posting, but you can easily find visual examples of each of the issues that I mentioned.
