I'm late to this party (as usual), but I just had to add... the maroon bottled Meguairs quick detailer (the stuff you find at Target, Autozone, etc) is the best spray bottle I've found. I buy the stuff, use it for clay lube, rinse out the bottle when it's gone, then relabel it for whatever I need. The bottle has the most uniform, even spray pattern I've ever seen. If you need a really fine micro-mist (like for a WOWA sealant), you can squeeze the trigger faster.
I really like those maroon Meg's QD bottles. Better than any aftermarket spray bottle I've tried yet. (Although I have yet to try those pressure-type ones.)