PG 2 is, honestly, a great game and a classic. I pumped about a trillion hours into it once upon a time. If this were 1997 and it was brand new, I wouldn't hesitate to tell you to get it. Even today, it's such a solid, challenging, enjoyable turn based tactical that I can't genuinely tell you *not* to get it
Personally, though, I now find it lacks a lot of the charm of PG 1 for some reason - I may be the only one, but I genuinely miss the little attack animations from the first game and some of the more simplistic systems. Subjectively speaking, if I was going to spend $13 on one or the other, and take a slight risk it might not work at all, I would 100% pick the first.
More objectively speaking, though, I'm just not sure why you'd buy this. OpenGeneral is a free, open source remake of PG 2 that does all the same things, a little bit more, and is free. It also allows for fairly easy modding, and tons of different eras, equipment sets, and scenarios are out there for downloading. While I actually like PG 2's older-style UI and graphics more, it's hard to say there's a lot to recommend it to most people over the more modern, less expensive alternative.
Personally, I hope GoG gets PG1 or one of the related games set in the Pacific theater on here instead - OpenGeneral doesn't emulate them quite as well and I'd have a much easier time recommending them as unique experiences for $10-$15.
That said, if you don't really care about the extras of OpenGeneral, don't like the presentation of it, or simply want to play a really, really good old game, I will, again, not ever tell you this isn't actually WORTH the small price tag.