Yeah, it's worth it. Since I obtained ToT, over 3 years ago, I haven't considered going back to the older versions. These days, you get a dirt cheap, upgraded version of, what is for many people here, a favourite game engine. Why wouldn't you want an upgraded version? Considering its enhanced scenario possibilities, I'm really surprised that many designers have chosen to ignore it.
I guess the two main issues to consider here are multi-player and the availability of scenarios. The most popular (but not necessarily the best) version of Civ2 is MGE, so if multi-player gaming is important, MGE might be the way to go. ToT also supports multi-player, but it's not back-compatible with MGE. Scenarios for ToT are also fairly scarce, with most being mere modifications of the standard rules. There are, however, a few ToT scenarios currently in development. So again MGE has the edge here.
To list the advantages of the ToT engine, I'll just quote myself from another thread:
Off the top of my head: it supports 15-bit colour, animated sprites, up to 80 different unit types, up to 4 maps/game, 96k events file, increased macro functionality, expanded Civilopedia, and additional unit abilities and control over the tech tree.
The following is a list of my main gripes with the ToT engine (compared to other versions): aggressive diplomacy model (same as MGE) when compared to FW, the conspicuous and inflexible health bar (although Mercator's
SpriteGen utility helps in some situations) and the dog ugly default graphics (most of which I've changed, although unfortunately there is very little 24-bit graphical material for ToT on the Internet most of it's regurgitated 8-bit stuff from the older versions of the game). There are a few other issues which don't bother me, but which may bother others: no scenario editor, no map editor (Mercator again
has solved this), no Wonder movies and no combat animation. There may be more that escapes me at the present I don't own MGE and it's been a long time since I played FW.
My guess is that, considering the price these days, the main factor contributing to ToT's lack of popularity is its lack of popularity a type of positive feedback effect. It's also old. So who's going to take the plunge?