I'm curious what type of subscriber numbers you are getting on your 450i setups. Connectorized or integrated? What size of sector antennas if you are using something other then 90 degrees.
We currently have a total of 6 450i integrated out there with the max number of subscribers being 15.
We've also deployed a 450i connectorized with an omni that has 8 subscribers and seems to be doing quite well.
This is a tough question to answer because there are so many variables involved. A great way to figure out about how much bandwidth you should be getting is to use LinkPlanner and dump a Google KML of your tower and client locations (either existing or proposed) and it will tell you what your aggregate AP capacity will be along with each client's bandwidth.
If you want something a little easier to work with, Cambium's also provided a PMP450 Capacity Planning guide, located HERE. You just plug values into a spreadsheet and it will spit out estimated capacities.
I'm not really looking for bandwidth. I'm curious how many clients people have and are still experiencing what they consider a good outcome. I know that really does have a lot of variables, but if there is a consensus that 30 people start to bog down a 450i I'd be curious to know that.
Again, it's very difficult to answer this question due to all the variables. That being said, we typically limit the number of subscribers on an AP based on the channel width. Keep in mind, this isn't a hard limit, and if we get to that line in the sand, we'll review the frame utilization to see if there's room for more subscribers.
So again... this is completely dependant on MY set of variables... BUT we usually use the following limits: