You need to be realistic about what you want to search for while in that city. You're not going to look for all (for example) 3,000 caches in that area. Filter your PQs to only return traditional caches with a difficulty <3 and a terrain <2.5. When traveling in a new area, I'm unlikely to have the desire or time to search for anything more complex than that, so there is no need to even download them. Besides, most GPS's can only hold 500 to 1,000 caches at a time anyways.
I only want to search all 2500 results with 1 query. Yes, from that all I will find cca. 5-10, but I don't know exactly where I will be there next day. Yes, I can divide in 5 queries, with different origin, difficulty etc, but it takes a lot of time, and the results must overlap to be sure that I have all. This I've done for my home location, but can't do every time for every place where I go next day or (sometimes) in few hours.
It's worthless restriction, which I can't realize, in these days, when computers' performance is very high
My GPS can hold 10000 waypoints, so there is no problem.