It's no secret that TS2015 DLC is ridiculously overpriced. Unless you're made of money you probably do the same thing that I do and buy as many add-ons as you're interested in as soon as they go on sale. If, like me, you blind-bought a good amount of DLC for this game not knowing what it was in the past, you're probably also quite keen on reading as many reviews for the trains you're wanting to spend your hard earned money on as well.
During the march madness sale I got the WSR and WSR Diesels twin pack for half its normal price. At that price point, I can definately say that it's worth it. I'm more of a steam train guy but I certainly enjoy messing around on the occasional diesel engine as well, and when you've got that urge this pack scratches the itch quite nicely.
The Class 03 included in this is an absolute blast to drive and one of my favorite diesels in the game. It has a five-position gearshift in addition to the usual reverser/throttle/brakes which means one more thing to have to keep in mind when you're using it. It's a blast to quick drive and can haul quite a bit more weight than you'd think looking at such a small engine. It also has siderods, which is a plus if you're like me and like watching all the mechanical parts doing their thing. Do note, however, that if you have the (actually quite good) Doncaster Works DLC, you already have a Class 03 shunter, though do also note that this type is in a slightly different livery and (at least on my terrible toaster of a computer) this one looks higher-resolution.
The Class 47 is a sharp looking diesel. It takes a bit of finesse to get the thing to go at a constant speed but once you've gotten the trick down it's quite a fun one to drive. The inside cab view seems (to my relatively untrained eye) to be modeled well, though being an American I haven't had the chance to see an actual one for comparison.
The sounds on these sound good to me at least, both having distinct horns and engine noises. I'm not as much of a stickler as lots on here are about sounds simply because I've never actually heard what the real ones sound like, but I didn't notice any glaring errors or anything.
The scenarios included are my only real gripe about this pack, namely that there simply aren't very many. Of the three, the first one is just a tutorial on how to drive the Class 03 (which is probably worth doing, as the gearshift takes some getting used to), which takes all of five minutes. The other two, one for each loco, are very fun and relaxing. Neither are particularly challenging, though the WSR route is eye-catching as ever.
I'm not particularly adept at getting gold medals or anything but I performed admirably meaning folks who have been doing this longer than I have will have no trouble with them. Of course, the workshop has more scenarios if you'd wish to get them, but of course you also need to own basically every DLC for a particular route and then some to actually play the vast majority of them.
All in all, probably my favorite diesel-based addon, and a good addition to my favorite route in the game. Definately worth picking up on sale, but if you have the WSR and absolutely *have to* have a good addon *right now* and don't mind spending twenty dollars I could certainly see you having fun with it, particularly if one is as big of a fan of messing around in quick drive as I am.