The SD70 is probably my all time favorite loco, aside from the NS GP-38 (which was the first loco I ever fell in love with as a kid). I've since become a fan of BNSF, and I've really been wanting to add that livery to my stable.
Some people might complain that it uses the default sounds from the stock UP SD70. For me this is okay, since I really love the sound of the engine. I like to sit at idle with the reverser in neutral and ramp up the engine just to hear it. Sounds almost like an airplane or a really loud spaceship gettingt ready to take off! The horn is by far my favorite. Out of all the locos in RS/TS, this is the only one that sounds like it has some cohones. It's loud, and lets you know it's there.
There are several variants of the SD70, as detailed in the store's page. One thing I noticed, is that there are two distinct bells. I think one is from the stock UP SD70, which is okay. The other one sounds better, and you'll find it on most of the other variants in this pack.
I thought the BN Executive livery (White and Green) was a nice touch, and I really enjoy looking at it when I get tired of the standard pumpkin livery. This pack also give me my first Norfolk Southern loco for TS, and I'm really looking forward to expanding my NS fleet soon.
Having said all of that, there are somethings I was disappointed with. First, was the fact that the headlights don't work properly. You can go to an external view and see them come on, but they don't cast any light, whether you're in the cab or outside. This makes night driving rather pointless. This is the biggest peeve that I have with this pack. I really wish the developer would fix this.
Second, I wish there were more working lights for this loco. I would like to have seen flashing ditchlights, interior cab lighting, and perhaps step lighting. These are minor things, but even the stock ES44ac has cab lights and interior lights.
As noted in the store's page, this DLC has been out for a couple of years now. I would really have thought that the developer would have at the very least addressed the issues with the headlights by now. Seriously, this is a huge disappointment. While I don't often operate my locos at night, I occassionally do like to break out of the norm and take on a different challenge. Guess I won't be doing that with this loco. Sigh...
Anyway, I still highly recommend this DLC. Despite a couple of things that need to be fixed, these really are nice locos. I operate them often, and I really enjoy the look and sounds of these awesome locomotives. A must have for the serious collector!