How useful are watchtower upgrades in Die2Nite

I've just completed my third town (18, 14 & 3 days, respectively) and in all three towns we never once upgraded the watchtower. From reading the descriptions it sounds like a worthwhile upgrade if you're in a town with a lot of expeditions or scavengers. Has anyone seen this to be the case? If not, what has your experience with it been?

Obviously Defense is King in Die2nite, but I've found well organized expeditions greatly increase the amount of resources a town is able to provide, as well as the number of defensive items it is able to find, thus directly increasing the amount of defense a town can produce.

Edit:

I should also clarify I'm interested in upgrade levels 4 & 5: Allowing citizens 1 & 2 km away from town to return for free.

Benefits I see:

• You can now plan 19 & 20 AP Loops
• Builders can auto-search outside of town for logs/scraps for 1 & 2 AP (as opposed to 2 & 4 ap)
• You can run 11 & 12 AP loops without getting thirsty.

Solution 1:

In my current town (strange community of crows), we had a big debate on it, and we decided that because we had plumbing, the watch tower is not that important since we have a kill team go out with a marked path everyday to clean out the renewed zone to make it safe for the scavengers anyway.

There is really no purpose for scavengers to go wandering off aimlessly beyond the first few days. Instead, we spent our upgrade on more important things, namely search tower, defensive focus, workshop, and upgradable wall.

The only time I'd see that the watchtower is useful is if your town has no scouts and you are having trouble finding the last few buildings on your map or you don't have plumbing/search towers.

Updating in response to Thechoyce's comment: Upgrading the watchtower to level 4 or 5 to take advantage of the AP savings requires 4-5 days of not upgrading something else.

First, let me say that there is no need for builders to scavenge next to town, by day 12 we already had enough raw wood/metal to build every building, our limiting factor (probably for most towns as well) is N&B, depleted zones don't yield those.

Lets run some quick numbers using my current town: We have roughly 12 full time scavengers (both heros and none heros), and 18 builders.

For watchtower upgrade 4, that saves us 12 ap per day. 24 for upgrade 5

Assuming we went straight for watchtower from day one, and we are currently at day 15 (we will see no benefit until day 4), we will save:

For watchtower upgrade 4: 12*11 days = 132 ap

For watchtower upgrade 5: 11 + 24*10 days = 251 ap

Here is what we would be potentially giving up: Defensive Focus (from 5 - 1): we currently have ~100 defensive items in the bank, this would cost us 600 defence, which would mean we would have died last night, so definitely not. Also, there is absolutely nothing you can build for 251 ap that yields 600 defence.

Search Tower (from 5 - 1): The entire map has been depleted since day 5 on, and there would be no way we would have as much defensive items and weapons without the search tower, so that's out again.

Workshop (from 3- 1) & Upgradable wall (from 3 - 1): 71 defence: 2 upgrades on the workshop saves us 14% of all building ap, just adding up the buildings we've completed since then (roughly estimated at a cost of 1000 ap, false town + mega pump being the big ones), we saved 140 ap, so its a wash with WT4, but that's with only 2 upgrades into workshop as compared to 4 in watchtower. However, add in the 71 defence from the two upgrades to the wall, it tips the scales in favor of spending it on these upgrades instead of the watchtower.

Finally, we are currently fast approaching the point where the only things we can build require nuts and bolts (of which we are short by ~25 on), all the AP savings in the world can't do anything if we can't build anything. I'm not saying the watchtower is bad, and I have no way of knowing how much more we can find if we did extend our expeditions from 18 ap out to 20 ap, but from the point of view of this town, it certainly isn't worth the upgrades.

Solution 2:

If you're aiming for surviving longer than 20 days, defense items are the only important factor! At some point you have built all defense buildings, and the zombies are still increasing every day. The only way to increase the defense further is to collect more defense items.

The watchtower allows you to plan expeditions better, together with the improved map you know were the zombies are and can ensure that you always control the zones you pass through. On the higher levels the watchtower also allows to increase the distance from town you can explore.

The question now is not whether the watchtower is useful, it definitely is, but is it more useful to the survival of the town than competing upgrades?. And you cannot isolate the levels 4&5 of the watchtower, as you have to take levels 1-3 before that and if you're already that far you will upgrade the watchtower fully anyway. The question is, are those 5 upgrades better spent for defense upgrades?

The watchtower is very useful, but you can offset the disadvantages of not having it through organization. If you have enough scouts, you'll know where the zombies are. And you just need to get your expeditions large enough to never lose control of a zone.

So, if you're confident that you can manage the level of organization in your town necessary for that, you can skip the watchtower. This will allow you to upgrade all of the defense constructions. Usually that is only possible in a meta coalition town, where an established group plans the whole thing.

If you can't organize the people like that or don't have enough heroes, the watchtower can be extremely useful.

In my last town in the german version of Die2Nite, we lasted 24 days and didn't upgrade the watchtower once.