two would be a whole lot of water...lol
Are you replacing a ladder truck?
What do your mutual aid companies have?
What is your typical truck company need on the fire ground? If you don't currently have a ladder, what fire ground need is driving the purchase?
Tower - Good working platform, excellent ability to deliver master streams, generally less compartment space (midmounts), bigger, heavier devices require bigger, heavier chassis and more maintenance costs.
I would say you need to look at everything and weigh things out, seems like a few more options turned up on this thread moreso than just a straight stick or platform. One being the option of a quint with a 75' stick, which if the current ladder height sufficed now, may be your cheapest option ans still replace two rigs with one.
Although, it helps to look towards the future and try and plan ahead, especially with a long term purchase as a truck. Is a 65' really sufficient right now or would having a 100' be a better option? It sounds like you guys are also looking towards a quint to replace two rigs, so it comes down to that option too, you lose a lot of storage space with a quint as opposed to a truck, so if you are only the truck in the area for 30 minutes, can you afford to lose equipment that having a quint will do? Yet, if use is moreso for aerial streams, do you really want to tie up a pumper to supply water for a truck?
We currently have 2 platforms and one straight stick. The platform allows for a couple people in the bucket and can control operations from the tip. The platforms have multiple outlets for hose connections so the aerial can be used as a mobile standpipe, whereas the stick has one outlet. As mentioned there can be two master stream devices on a platform as opposed to one on a stick. The stick has a "rescue" and "water tower" lever that controls the water pipe, so you don't inadvertantly crush the waterway for a rescue, the platform, you don't have to worry about that since the ladder stays away from the building.
However, while we do use the platforms more, the straight stick still gives plenty of options at a lower cost than a platform. You can still accomplish many options with a stick like you can with a platform, it comes down to training and what you really want. Another thing you may want to look into is funding from other communities. If you are running MA or even automatic aid, with the ladder often, perhaps that is something to look into as well. The costs can be split to reduce the burden on your dept and other depts can benefit as well. This also gives you a chance to go with a better option that may be overlooked because of cost.
In the end, the platform gives a more stable option to operate from, you can have a couple FF's at the tip so a rescue isn't just on one FF, and also gives a second set of eyes. The platform can be more stable since they tend not to be affected as much by wind, etc, whereas a stick can bounce more. While a stick gives many of the same options on a limited basis, so it comes down to what you think works best for your dept and area.
Another consideration is maneuverability.
A tractor drawn aerial beats mid-mounts, rear-mounts, and platforms for maneuverability hands down.
The trade-off is that it takes two drivers and the driver training requirements are more difficult and take longer if done right.
Most manufactures will bring a demo to your dept. to try out for a day. You might look into this. Have a Platform brought then a stick. A tiller is nice but they cost and there is the training as was mentioned.
If your dept. doesn't do alot of truck work you might look at the platform. You really have to
be comfortable working off a stick, especialy at high angles. It can get tricky doin work off a stick plus getting a victem down is also tricky.
Like I said, try to get some demos brought to you and try them out in your area. Fly the ladder set up around your area. See what is going to work best for your dept.