"Also, what is the estimated service life of a typical bolt action rifle?"
A really long time with minimal care and minimal abuse. Many bolt actions have low round counts. High round counts usually mean replace the barrel and shoot some more. Unless a bolt action is abused and not cared for it should be around for generation. My dad got a Rem 700 and it is on the 3rd generation of Whitetail kills.
Until your post I had never seen the 'Night Train'. It is getting trashed on the net. I think a lot of that is jumping on the band wagaon of trashing a product without any real knowledge of it. If you buy one and is turns out bad then what?
I didn't find a price on the 'NT'. The scope is probably not all that great. It may be a good starter package that will require upgrading later. Handling one might tell you something. I wouldn't let conjecture talk me out of one.
Other options are Weatherby Vaguard/Howa, Savage or Rem 700. As you already know the Savage and Rem have the popularity going for them. Marlin may be a consideration.
I got a used Rem 700 (I think it had never been fired) but was looking at new Savages. I got 2 stocks, 2 triggers, brass and dies, scoped rifle traded for an AR upper I had $500 into. I am a big fan of used (Pre-Owned). 1 of my triggers was a Jewell. Ignorance is bliss - I didn't know what a Jewell was til after I had one!!
I honestly don't have a preference and would not hesitate to get either a Savage or Rem. I have seen both shoot well with little work and handloads. I am a firm believer that the shooter/handloader is more of a factor than Rem vs Savage. Rifle fit would be a deciding factor. The stocks on the Savages are nice. I did like the advantage of the switching barrels on the Savage even though I might never utilize that feature.
I also have a Vanguard Sporter that is pretty impressive. I am setting up one for someone in .243 that is synthetic stock. The triggers are pretty good on them.