I like this approach. I would lean towards the Seiko because you should be able to find a store near you so you can touch and feel and get a sense for the build quality and how big/small the different sizes are when on your wrist. 
 

good luck and enjoy!

I literally just picked one of these up 2 days ago. I feel this is a great watch for the price and I’m lucky enough to be able to treat myself to it. 
 

Been in “Technology“ for 28 years. Everything from Linux systems engineer for an auction website to Outside Plant engineer for a large telecom company to my current DNS systems engineer for a large wireless company. 

It’s a 42. It fits a little big with the nato strap but sits really nicely on a bracelet. It’s the GL0083 

That does look good and goes well with the shirt!